Re: Issue 2223 in sympy: Rename top level apply_operators to qapply
Updates: Labels: -NeedsReview PassedReview Comment #3 on issue 2223 by Vinzent.Steinberg: Rename top level apply_operators to qapply http://code.google.com/p/sympy/issues/detail?id=2223 (No comment was entered for this change.) -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2000 in sympy: Inconsistencies with limit()
Updates: Status: Fixed Comment #4 on issue 2000 by Vinzent.Steinberg: Inconsistencies with limit() http://code.google.com/p/sympy/issues/detail?id=2000 This is in. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2222 in sympy: Matrix([Matrix, ...]) should check the row length of empty matrices
Comment #11 on issue by pr...@goodok.ru: Matrix([Matrix, ...]) should check the row length of empty matrices http://code.google.com/p/sympy/issues/detail?id= Yes, I mean slicing. Now I see that all variants of usage and generalization must be examined deeper. (I also have not looked and the current usage of it in Integration3) But I tend to separate classes with different behavior and to do not mix the code of them with the aim of `a single multi-purpose class`, especially when Python allow us to `mix them in usage` in convenient and right way. The heritage of the past (mathematics of past century, and even theory of group of 1930x) with no object oriented approach without that put the many questions. Additional info: Empty matrix in mathematics [1], empty matrix in matlab [2], also there is so called 3D matrix (which can by applied for multi-algebra ) [1] http://en.wikipedia.org/wiki/Matrix_(mathematics)#Abstract_algebraic_aspects_and_generalizations [2] http://www.kxcad.net/cae_MATLAB/techdoc/matlab_prog/f1-86359.html -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 828 in sympy: In sympy.geometry many docstrings are not good enough
Comment #9 on issue 828 by gdrummo...@gmail.com: In sympy.geometry many docstrings are not good enough http://code.google.com/p/sympy/issues/detail?id=828 I'll fix the Triangle docstrings. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 950 in sympy: put all _sage_ methods to one place
Comment #5 on issue 950 by pr...@goodok.ru: put all _sage_ methods to one place http://code.google.com/p/sympy/issues/detail?id=950 As I understand the same (about Ronan's Having to hack the core) is with _pretty_ and so on. Is not this? I cite the old correspondence (the answer of Aaron to my first letter in this mail-list, on wich I have not time to answer myself): http://www.mail-archive.com/sympy@googlegroups.com/msg06813.html Aaron wrote: By the way, I am assuming from the name and from the fact that you want to do this that MyClassExpr is inheriting from Expr. How would this work if your class is a part of some other SymPy class, like an Add or a Mul? I'm not too familiar with how it works, but I know that pretty() internally has some bounds stuff to make the 2-dimensional printing work correctly with each other (like if you have an expression that is 3 lines tall surrounded by parentheses, then you need parentheses that are 3 lines tall). Would your idea work seamlessly with this? The current situation is that: * we have base class (Basic with _sage_, or Expr with _pretty_), others inherited classes (SameExpr), and the processor (sage.var or prettyPrint), somewhere. But processor have its own internal station. * while the task of process with sage or pretty print arise then processor created for parsing expression in recurrence (or more complicated) mode. * when processor parse SomeExpr then #1 it check if in Processor class or Basic class the method like _pretty_SomeExpr exists This way allow to the processor use its own state's variables, which it keeps. if #1 is not then: #2 it check SomeExpr._pretty_ method existence and call it But the situation for #2 as that that while calling SomeExpr._pretty_ he do not supply processor (and state) itself. In such a way the dilemma is raised how to isolate code and where to place implementation: On the one hand SomeExpr._pretty_ do not know about precise processor implementation On the other processor do not know precisely about SomeExpr. The variant which had chosen is to place implementation to the processor, or to base Basic._pretty_. My opinion is that #2 must be corrected to permit calling with additional unnecessary parameter - processor. In this way I can fully create class with _sage_ or _print_ handlers in isolated mode, without modification of any core files of Basic or Epr, and at the same time I can operate with the state of processor, and (only if it really needed) I can also modify only processor code. I suppose that the task which described here is solved by adding a two lines (near #2 checking), and by adding unnecessary parameter in _pretty_ definition of *all classes*. I am going to make experiment about this reorganisation of architecture, but before the idea must be discussed - all remarks are welcome. May be it must general way for _handler_ like handlers, or there are specificities for _sage_ or _pretty_ ways. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 341 in sympy: sympy-merge: matrices: dirac conjugation is broken
Comment #9 on issue 341 by ness...@googlemail.com: sympy-merge: matrices: dirac conjugation is broken http://code.google.com/p/sympy/issues/detail?id=341 physics/matrices.py provides a working replacement for Pauli called msigma. Whereas pauli tries to implement the pauli algebra directly (and fails for things like Product(Number, Pauli)), msigma just creates the relevant matrices. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2224 in sympy: Number('5').__class__ == Real
Comment #4 on issue 2224 by mrock...@gmail.com: Number('5').__class__ ==
Real
http://code.google.com/p/sympy/issues/detail?id=2224
Issued pull request through github.
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Re: Issue 1242 in sympy: Simplifying of complex exponentials
Comment #3 on issue 1242 by pr...@goodok.ru: Simplifying of complex exponentials http://code.google.com/p/sympy/issues/detail?id=1242 Yes, I indicate that this works in current SymPy. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 1935 in sympy: Sum doesn't rebuild itself
Comment #4 on issue 1935 by pr...@goodok.ru: Sum doesn't rebuild itself http://code.google.com/p/sympy/issues/detail?id=1935 I indicate that this works in current SymPy now: expr = Sum(x**k, (k,1,5), (x,0,9)) expr Sum(x**k, (k, 1, 5), (x, 0, 9)) expr.func(*expr.args) Sum(x**k, (k, 1, 5), (x, 0, 9)) -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #1 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 A few of the matrix norms seem to depend on undeveloped machinery (i.e. SVD). Is it best to throw NotImplementedErrors or to wait on this all together? Can anyone think of a method to find max_x(|Ax|/|x|) A a matrix, x a vector without computing the largest singular values? Actually, does anyone know of an algorithm to compute the SVD analytically? The method I'm familiar with is iterative. Is this a solvable problem? -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 1935 in sympy: Sum doesn't rebuild itself
Updates: Status: Fixed Comment #5 on issue 1935 by asmeurer: Sum doesn't rebuild itself http://code.google.com/p/sympy/issues/detail?id=1935 I think this was fixed with issue 2070. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2222 in sympy: Matrix([Matrix, ...]) should check the row length of empty matrices
Comment #13 on issue by pr...@goodok.ru: Matrix([Matrix, ...]) should check the row length of empty matrices http://code.google.com/p/sympy/issues/detail?id= Thanks, I understand the model now, but it seems that it is extension. May be similar as complex extends reals or other fields, to permit some operations. But not at the expense of reals reorganization itself. However, this issue has a low priority, and I think it can be discussed further, in more proper time. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 1242 in sympy: Simplifying of complex exponentials
Comment #5 on issue 1242 by pr...@goodok.ru: Simplifying of complex exponentials http://code.google.com/p/sympy/issues/detail?id=1242 In current master: In [1]: c = cos(x)._eval_rewrite_as_exp(x) In [2]: t = tan(x)._eval_rewrite_as_exp(x) In [3]: simplify(c*t) In [1]: c = cos(x)._eval_rewrite_as_exp(x) In [2]: t = tan(x)._eval_rewrite_as_exp(x) In [3]: simplify(c*t) Out[3]: (I - I*exp(2*I*x))*exp(-I*x)/2 In [5]: simplify(c*t).expand() Out[5]: -I*exp(I*x)/2 + I*exp(-I*x)/2 It is correct, but .expand() usage is needed. But (3 hours ago and now) I have tested in my fork, where `simplify(c*t)` yield `-I*exp(I*x)/2 + I*exp(-I*x)/2` straightly, without expand() Also, I do not the precise politics of `simplify` what to do simpler (Out[3] or Out[5]). In any case, the tests have to be presented in sympy about it. So, formally, issue is not fixed now (no test). Additionally: (it is out of this issue, but may be another new), to avoid many similar problems with comlexes - it is a question, I will cite myself: Complex numbers: I observe that there are two ways to operate with them. Pure symbolical way (with assumption option): I can operate symbolical with complex variable with the help of standard operations (multiplicity, abs, conjugate and so on): Another way with the aim of I symbol: I can observe real and imaginary parts, and with the aim of I behaviour operations are maintaining: E.g. for 1 + cos(x) + I + sin(x)*I if I multiply this by I, than sympy scan every sub-expression in Add class and every sub-expression is multiplied by I. I wonder that there is no class of complex number as like as Rational(p/q), which tracking real and imaginary part. In this way, this operation would be separated: 1 + cos(x) moved to imaginary field of class and 1 + sin(x) to real field of class. The reason is not only for complex number, but for one way to operate with para complex numbers (where I**2 = 1) or dual numbers (I**2==0 ), and for extension for other dimensions (quaternions, Clifford algebra and so on). But I am not sure is it a poper time for rising it right now. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #3 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 Pull request issued https://github.com/sympy/sympy/pull/156 Included is Matrix.norm, Matrix.singular_values, Matrix.condition_number I didn't include the main SVD work. I'll set up another issue for this. Comments appreciated. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #5 on issue 2225 by p...@goodok.ru: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 I have looked at the code (one eye), nice. Some *preliminary* remarks, I put there -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #4 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 Sent in a Pull request https://github.com/sympy/sympy/pull/156 This includes work on Matrix.norm, Matrix.singular_values, and Matrix.condition_number I left the main SVD algorithm for another issue. Some basic test-cases are in matrix/test/test_matrices.py Comments appreciated -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #6 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 Response to an e-mail comment. I chose to make the standard matrix norm the spectral norm. This matches the standard vector 2-norm mathematically. The spectral norm is the matrix equivalent of the 2 norm. This has nicer mathematically although poorer computationally. This deviates from numpy, which chooses to use the easily computable Frobenius norm as standard. Should we be consistent with Numpy or consistent with Mathematics? -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Updates: Status: NeedsDecision Labels: NeedsReview MRocklin Comment #7 on issue 2225 by asmeurer: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 Maybe someone with more knowledge of it could decide about that norm thing. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 1117 in sympy: Setup buildbot (again)
Updates: Summary: Setup buildbot (again) Labels: -Priority-Medium Priority-Critical Comment #8 on issue 1117 by ronan.l...@gmail.com: Setup buildbot (again) http://code.google.com/p/sympy/issues/detail?id=1117 I'm raising the priority on this. Stuff like this is just too embarrassing: http://groups.google.com/group/sympy/browse_thread/thread/d64f81c35285933b -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #10 on issue 2225 by asmeurer: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 You should not edit the mpmath files. mpmath is a separate library that we include with SymPy, so any changes there should be backported to mpmath. This change actually does belong in sympy/matrices/matrices.py. From what I understand, symbolic norms are planned, but are currently not possible due to the lack of a Max function that works for an arbitrary number of arguments in SymPy. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #11 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 @asmeurer: I don't think there is such a thing as symbolic norms. Correct me if I'm wrong. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #15 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 To be clear I don't think this will often be useful (except for simple educational cases). As long as we have the ability to compute eigenvalues symbolically though why not put it in? It's no less silly and not very much code. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #16 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 As long as we have the ability to compute eigenvalues symbolically Could you elaborate what you mean by this ? You're right that's not much code, but we do have to consider its usability. We can't put in code that's not usable. Ideally, norm calculations should be sent to mpmath to be solved. But one idea for symbolic norms is to compare matrices. I'll elaborate. A matrix A defined in terms of symbol x, and another matrix B, which is either numeric or defined in Symbol y, Consider the question, for what range of x and y, is A B or A B. This is not a trivial project. And there would be many more cases. This is just the simplest example. That would be a good symbolic matrix addition. Ask if you want clarification. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #17 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 OK, I get what you mean by As long as we have the ability to compute eigenvalues symbolically Yeah, I'd let the core team decide if this is important enough to be put in, considering we don't want code cluttering. -- You received this message because you are subscribed to the Google Groups sympy-issues group. To post to this group, send email to sympy-issues@googlegroups.com. To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en.
Re: Issue 2223 in sympy: Rename top level apply_operators to qapply
Updates: Labels: -NeedsReview PassedReview Comment #3 on issue 2223 by Vinzent.Steinberg: Rename top level apply_operators to qapply http://code.google.com/p/sympy/issues/detail?id=2223 (No comment was entered for this change.) -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2223 in sympy: Rename top level apply_operators to qapply
Updates: Status: Fixed Comment #4 on issue 2223 by Vinzent.Steinberg: Rename top level apply_operators to qapply http://code.google.com/p/sympy/issues/detail?id=2223 (No comment was entered for this change.) -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2000 in sympy: Inconsistencies with limit()
Updates: Status: Fixed Comment #4 on issue 2000 by Vinzent.Steinberg: Inconsistencies with limit() http://code.google.com/p/sympy/issues/detail?id=2000 This is in. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2224 in sympy: Number('5').__class__ == Real
Updates:
Labels: NeedsReview MRocklin
Comment #5 on issue 2224 by asmeurer: Number('5').__class__ == Real
http://code.google.com/p/sympy/issues/detail?id=2224
In the future, make a note of the pull request number here on the issue.
This one is at https://github.com/sympy/sympy/pull/154.
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Re: Issue 2225 in sympy: Enhancing Matrix Norm
Updates: Status: NeedsDecision Labels: NeedsReview MRocklin Comment #7 on issue 2225 by asmeurer: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 Maybe someone with more knowledge of it could decide about that norm thing. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #8 on issue 2225 by p...@goodok.ru: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 I am not sure about what to do now, I just rise up question. I will answer tomorrow. And do not worry, as I begin to discuss your GitHub pull request I automaticaly joind to your pull, and receive all your answers by the mail. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #9 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 This approach only works for purely numerical matrices. Check out sympy/mpmath/matrices/matrices.py That is the library that deals with numeric matrices. Any numeric algorithms would be preferred to be added there, and not in sympy.matrices/matrices.py, the one that deals with symbolic matrices. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #10 on issue 2225 by asmeurer: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 You should not edit the mpmath files. mpmath is a separate library that we include with SymPy, so any changes there should be backported to mpmath. This change actually does belong in sympy/matrices/matrices.py. From what I understand, symbolic norms are planned, but are currently not possible due to the lack of a Max function that works for an arbitrary number of arguments in SymPy. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #11 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 @asmeurer: I don't think there is such a thing as symbolic norms. Correct me if I'm wrong. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #12 on issue 2225 by asmeurer: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 Certainly there are. They are as defined in the OP. So, for example, the 2 norm of the vector [x, y, z] is sqrt(x**2 + y**2 + z**2). Just about anything in mathematics that can be done numerically can be expressed in a symbolic way. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #13 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 What I mean is, Norms make sense only when the matrix is completely known, and thus when it is purely numerical. 'Norm' aims to associate a number with a matrix that is a reasonable measure of its largeness, so that we can compare matrices. Adding norm to symbolic matrices is not very useful, since most norm definitions are eigenvalue-based algorithms, which itself is a purely numerical matrix property. We can however implement some trivial norms, which are not based on eigenvalues, but doing so for a symbolic matrix will just return a complicated expression for norm. Doable, but not very useful. I understand that we're not allowed to change mpmath, but this idea does belong to mpmath. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #14 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 I e-mailed this to the list, it doesn't appear to be coming up. I apologize if a repeat post happens. Example: Spectral norm of a matrix (standard 2-norm) can be defined as the largest singular value of that matrix. This is the maximum amount that the matrix can grow the 2-norm of a vector. We can define the principal singular value of a matrix A as the square root of the largest eigenvalue of (A.T * A) (real). We have symbolic methods to compute eigenvalues (you learned them briefly in high school) so this is alright so far. The issue I'm having is that I need to return the largest of the eigenvalues and I don't know apriori which that is if things are symbollic. Ideally (I think) I'd return some sort of Max object like how we deal with Adds and Pows. consider A = Matrix([[1 0], [0, x]]) norm(A) == max(1,x) #I'm not sure which it should be yet. We can decide once we have a value for x. sherjilo... you're right that they end up coming out as very complicated expressions. For even very simple matrices they're often hideous. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #15 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 To be clear I don't think this will often be useful (except for simple educational cases). As long as we have the ability to compute eigenvalues symbolically though why not put it in? It's no less silly and not very much code. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #16 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 As long as we have the ability to compute eigenvalues symbolically Could you elaborate what you mean by this ? You're right that's not much code, but we do have to consider its usability. We can't put in code that's not usable. Ideally, norm calculations should be sent to mpmath to be solved. But one idea for symbolic norms is to compare matrices. I'll elaborate. A matrix A defined in terms of symbol x, and another matrix B, which is either numeric or defined in Symbol y, Consider the question, for what range of x and y, is A B or A B. This is not a trivial project. And there would be many more cases. This is just the simplest example. That would be a good symbolic matrix addition. Ask if you want clarification. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #17 on issue 2225 by sherjilo...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 OK, I get what you mean by As long as we have the ability to compute eigenvalues symbolically Yeah, I'd let the core team decide if this is important enough to be put in, considering we don't want code cluttering. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #19 on issue 2225 by mrock...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 I think it can be useful. Remember that CASs like SymPy can handle easily very large symbolic expressions that you could never feasibly handle by hand. Also, just because something *can* be large doesn't necessarily mean that it *will*. If someone gives it a large symbolic non-diagonal matrix, then it might be large. But there are cases where it won't (like if the matrix is small, or if it is diagonal). There are other functions that can also blow up. For example, if you try computing integrate((a*x**2 + b*x + c)/(d*x**2 + e*x + f), x), it will take about an hour to finish, and the result will be several full-screens of output (I think you might have to do this in my integration3 branch due to a bug in master). But that doesn't mean that we should ban integrate(). In fact, it is one of the most important functions in SymPy. It is not to difficult to come up with other examples where even the input is small, but the output will be large (like expand((x + y + z)**1)). Also, don't assume that you know what will and will not be useful to people. It may surprise you what various things are applied in more advanced mathematics (or physics or whatever) that you don't even know about. An example I can think of off the top of my head where symbolic eigenvalues would be useful is in classifying systems of second order PDEs with symbolic or with non-constant coefficients. Based on the signs and other properties of eigenvalues, it will have a different classification, elliptic, parabolic, or hyperbolic. If the coefficients are non-constant, different regions of the domain will have different types. I think there are other methods that you can use other than eigenvalues to determine this for second order PDEs, but perhaps not so for higher order ones (this is something that I just learned recently in my PDEs class, so I hope what I just said is all correct). -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: Issue 2225 in sympy: Enhancing Matrix Norm
Comment #20 on issue 2225 by ronan.l...@gmail.com: Enhancing Matrix Norm http://code.google.com/p/sympy/issues/detail?id=2225 I think both Sherjil and Matthew make good points here. There are cases where you want .norm() to return an explicit result but if you consider a 100*100 matrix with a handful of parameters, trying to compute the norm will just kill the interpreter with an OutOfMemoryError after hours of thrashing, even though the numeric calculation would be nearly instantaneous. In that case, you actually want .norm() to return some Norm(matrix) object, so that you can get on with your calculations and obtain explicit values later on when you've specified the value of the parameters. The difficulty is to make sure that the calculations are done only when they're both doable and useful. Nobody actually cares about the explicit value of integrate((a*x**2 + b*x + c)/(d*x**2 + e*x + f), x), because it's always easier to do the computation for specified values of a,b,c,d,e,f than to use the explicit result. -- You received this message because you are subscribed to the Google Groups sympy-patches group. To post to this group, send email to sympy-patches@googlegroups.com. To unsubscribe from this group, send email to sympy-patches+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy-patches?hl=en.
Re: [sympy] GSoC 2011 - Oleksandr Gituliar
Oleksandr Welcome, my name is Oleksandr Gituliar and I'm a second year PhD student at The Institute of Nuclear Physics [1] in Krakow, Poland. As a physicist I mainly deal with theoretical calculations in QCD (namely, next- to-leading order corrections to solutions of DGLAP evolution equation and all stuff related to that like Feynman graphs, regularization techniques, factorization theorems, etc.) as well as Monte-Carlo simulations of different kind. Nice, your experience could be very helpful. As a programmer I'm involved in a freelance activity [2] as well as my personal opensource mini projects [3] and [4]. I'm mainly programming in Python and C/C++, however also familiar with Scheme. A more detailed list of projects proposals will follow soon as a wiki page, but briefly I can say that physics projects as well as symbolic mathematics are under my consideration. PS. Sending this letter I express my strong interest in participating in GSoC 2011. Here is what I suggest: * have a look at the ideas page on github (see recent threads for the link). * For QCD related things, I think it would be *very* interesting to implement SU(N), in a similar manner to how we have implemented spin (see sympy.physics.quantum.spin). * There are a number of other topics, such as second quantization that you may be intersted in. * I highly recommend digging into the code ASAP and starting to contribute before the application deadline. * Don't hesitate to ask questions! Cheers, Brian [1] http://www.ifj.edu.pl [2] http://www.odesk.com/users/Python-and-programmer-theoretical-physicist-see-http-gituliar_~~39097b1ddefc549a [3] https://bitbucket.org/gituliar [4] http://hg.tx97.net/gituliar/krkmc/summary -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC_Symbolic Quantum Mechanics
Dido, Welcome! My name is Dieudonne Nkulikiyimfura and I have been looking for a project to work on during this summer and I found that your organization have a quiet interesting project for me: Abstract Dirac Notation. In fact, I am a master student in Interdisciplinary IT at Konkuk University (South Korea) and I am a holder of B.Sc in Physics but I don't have experience in quantum computing, I am now using Java and C+ + languages. As I have seen, the project have been partially done, can I know its progress, how they proceeded and what is its next steps? There are many things still left to do. The best thing to do is to dig into the code, start playing with it and figure out what you are interested in. Start asking specific questions about the code a potential topics. Have you seen the ideas page? Cheers, Brian Hoping to hear from you soon, -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: One more GSoC Introduction
On Tue, Mar 22, 2011 at 6:51 PM, Ondrej Certik ond...@certik.cz wrote: HI Anatolii, On Tue, Mar 22, 2011 at 5:43 PM, weralwolf weralw...@gmail.com wrote: Can you write a few more words about the project? Which disturbance theory, how the corrections would be calculated and how sympy would be used, and which features will be improved? Ondrej Thanks for questions, Ondrej. Perturbation theory comprises mathematical methods that are used to find an approximate solution to a problem which cannot be solved exactly, by starting from the exact solution of a related problem. Perturbation theory is applicable if the problem at hand can be formulated by adding a small term to the mathematical description of the exactly solvable problem. For example if we should calculate approximation for hydrogen atom in magnetic field using eigenfunctions and energy levels calculate without field. Corrections will be calculated due to classic theory through perturbation matrix elements. More about http://en.wikipedia.org/wiki/Perturbation_theory_(quantum_mechanics) . Oh, I didn't know you meant perturbation theory by disturbance theory. I know what perturbation theory is. I even have some notes here: http://theoretical-physics.net/dev/src/quantum/qm.html#systematic-perturbation-theory-in-qm SymPy will be used as tool set for it, because there implemented large part of required functionality. Also I want implement working with creation and annihilation operators which will be good improvement, cause it simplify many calculations in quantum theory. There already is some implementation of the annihilation and creating operators in sympy.physics.quantum, but it surely needs improvements. Perturbation theory would be really cool, as those calculations are really tedious to do by hand. Definitely, I think lots of people would be interested in such a project. I would suggest you to try to play with the current quantum module in sympy and then see (in details) what things to improve and what exact steps would have to be done to implement the perturbation theory. Yes, we would be interested in perturbation theory, especially in an abstract sense, so a wide range of system, from single particle non-relativistic to many particle rel. could be treated. I would check out the existing code, especially the second quantization stuff and see what you think could be done. Cheers, Brian Ondrej -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Comments about GSoC projects related to sympy.physics
Hi, I hope everyone who is interested in the GSoC program is getting a feel of sympy's codebase and community. This year, we are getting a lot of interest, which is fantastic. A good number of folks are interested in various parts of sympy.physics and I have some thoughts for all of you. * Start to dig into the code now. The code in sympy.physics is non-trivial and will take a while for you to get to know it well enough to write a good GSoC proposal. * Hang out on IRC and ask us questions on the mailing list. * Look through the ideas page to get ideas on potential topics: https://github.com/sympy/sympy/wiki/GSoC-2011-Ideas * Aaron has a great blog post here about how to proceed here: http://asmeurersympy.wordpress.com/2011/03/18/sympy-is-a-google-summer-of-code-2011-mentoring-organization/ Cheers, Brian -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSoC 2011 - Oleksandr Gituliar
my name is Oleksandr Gituliar and I'm a second year PhD student at The Institute of Nuclear Physics [1] in Krakow, Poland. As a physicist I mainly deal with theoretical calculations in QCD (namely, next- to-leading order corrections to solutions of DGLAP evolution equation and all stuff related to that like Feynman graphs, regularization techniques, factorization theorems, etc.) as well as Monte-Carlo simulations of different kind. Nice, your experience could be very helpful. Thank you Mr. Granger. PS. Sending this letter I express my strong interest in participating in GSoC 2011. Here is what I suggest: * have a look at the ideas page on github (see recent threads for the link). In progress... * For QCD related things, I think it would be *very* interesting to implement SU(N), in a similar manner to how we have implemented spin (see sympy.physics.quantum.spin). Concerning SU(N) representations of the rotation group I agree that it would be extremely interesting to work on it especially in a symbolic/ analytical form. As for the same things in QCD, did you mean Lorentz group SU(N) representations (with bispinors, 4-vectors, relativistic objects with a higher spin)? * I highly recommend digging into the code ASAP and starting to contribute before the application deadline. * Don't hesitate to ask questions! Surely! PS. I'll let you know once I finish working on my idea list. Sincerely, Oleksandr. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSoC 2011 - Oleksandr Gituliar
Here [1] I started a wiki page with my ideas and proposals. Note it is not complete and is supposed to be constantly updated. Feel free to make any corrections and/or proposals. [1] https://github.com/sympy/sympy/wiki/GsoC-2011-Application-Oleksandr-Gituliar -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSoC 2011 Application
The first and third item would be useful to have, but they are not really big enough projects for a summer of code. The second one could be, though. I would need to see a more detailed plan on what you plan to implement to see if it is big enough. Aaron Meurer Actually it was one idea which include three smaller ones because they are connected with each other. The rough plan of implementation: 1. Implement pattern matching functionality. Function like Maple indets which can return the list of subexpressions of given type from given expression is required. e.g. indets(f(x)+2*x+sin(y+cos(t)),'function') should return the list f(x), sin(y+cos(t)), cos(t) This immediately give us the solution of the third problem (concerned with dsolve) 2. Implement function which return minimal list of linearly independent functions of one variable form given one. e.g. linind(cos(t+1), sin(t), cos(t)) should return sin(t), cos(t) This helps to solve the first problem. 3. Then singular function should be implemented. This function should return values of parameters which make given expression singular. e.g. singular(tan(c)*y/(d*(a+b*x)),(a,b,c,d)) should return (a=0, b=0),(c=Pi/2+Pi*N_1) This helps to implement parametrizer. 4. Implement parametrizer casemap which do the require operation parameter-wise e.g. casemap(dsolve, diff(f(r),r)=a*f(r)+b*r+c, (a, b, c)) should return (f(r)=C_1*exp(a*r)-b*r/a-(b+a*c)/a^2 , a!=0), (f(r)=b*r^2/2+c*r+C_1, a=0) the same method can be used for rank calculation using determinant method because A=Matrix((1, x), (1, 1)) casemap(det, Inverse(A), x) should return (1/(1-x), x!=1), (infinity, x=1) This solve the second problem, but it's assumed that ODE module is able to solve ODE's without checking of parameters. If it's not — the improvement of ODE module should be done first. This idea is not obligatory and if you need improvements of ODE or PDE module or anything else, I will be glad to help. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: Another GSoC Idea
On Mar 22, 11:31 pm, Aaron Meurer asmeu...@gmail.com wrote: I think this idea could work, but would like to see more details (anyway, there will need to be a lot more details in the application). Aaron Meurer At least it is possible to implement basic the most routine functionality 1. Generate infinitesimal operator of given variables 2. Calculate the extension of infinitesimal operator of given order 3. Calculate differential sequence of given equation (system of equations) 4. Apply the infinitesimal operator to the equation (system of equations) 5. Obtain system of determining equations 6. Calculate commutator and anticommutator of two operators Then some additional functionality can be added 1. Obtain the classification and determining equations for the classification problem 2. If tesor module allow – implement above functionality for arbitrary order of dependent and independent variable e.g. x = (x_1,...,x_n), y =(y_1,...,y_m), where n and m is unknown 3. If PDE module allow – solve the system of determining equations 4. If above is true – completely solve the classification problem in simple cases -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: Another GSoC Idea
On Wed, Mar 23, 2011 at 6:26 AM, Yuri Karadzhov yuri.karadz...@gmail.com wrote: On Mar 22, 11:31 pm, Aaron Meurer asmeu...@gmail.com wrote: I think this idea could work, but would like to see more details (anyway, there will need to be a lot more details in the application). Aaron Meurer At least it is possible to implement basic the most routine functionality 1. Generate infinitesimal operator of given variables 2. Calculate the extension of infinitesimal operator of given order 3. Calculate differential sequence of given equation (system of equations) 4. Apply the infinitesimal operator to the equation (system of equations) 5. Obtain system of determining equations 6. Calculate commutator and anticommutator of two operators For operators, commutators, etc., check out: sympy.physics.quantum.operator|commutator|anticommutator Cheers, Brian Then some additional functionality can be added 1. Obtain the classification and determining equations for the classification problem 2. If tesor module allow – implement above functionality for arbitrary order of dependent and independent variable e.g. x = (x_1,...,x_n), y =(y_1,...,y_m), where n and m is unknown 3. If PDE module allow – solve the system of determining equations 4. If above is true – completely solve the classification problem in simple cases -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSoC 2011 - Oleksandr Gituliar
Oleksandr On Wed, Mar 23, 2011 at 12:51 AM, oleksandr gituliar gitul...@gmail.com wrote: my name is Oleksandr Gituliar and I'm a second year PhD student at The Institute of Nuclear Physics [1] in Krakow, Poland. As a physicist I mainly deal with theoretical calculations in QCD (namely, next- to-leading order corrections to solutions of DGLAP evolution equation and all stuff related to that like Feynman graphs, regularization techniques, factorization theorems, etc.) as well as Monte-Carlo simulations of different kind. Nice, your experience could be very helpful. Thank you Mr. Granger. PS. Sending this letter I express my strong interest in participating in GSoC 2011. Here is what I suggest: * have a look at the ideas page on github (see recent threads for the link). In progress... * For QCD related things, I think it would be *very* interesting to implement SU(N), in a similar manner to how we have implemented spin (see sympy.physics.quantum.spin). Concerning SU(N) representations of the rotation group I agree that it would be extremely interesting to work on it especially in a symbolic/ analytical form. As for the same things in QCD, did you mean Lorentz group SU(N) representations (with bispinors, 4-vectors, relativistic objects with a higher spin)? I was simply thinking that when doing various types of computations in QCD, it would be useful for have access to all the SU(N) machinery in symbolic/numerical form. I had a look at your ideas page. A few comments: * Under the basic QM notation section. I think everything listed there has already been implemented, at least initially. Definitely have a look at the code for that. But there is definitely more to do, especially with continuous Hilbert spaces with differential operators. * Perturbation theory + variational methods. I would love to see a lot of detail here as we would very much be interested in this topic. Cheers, Brian * I highly recommend digging into the code ASAP and starting to contribute before the application deadline. * Don't hesitate to ask questions! Surely! PS. I'll let you know once I finish working on my idea list. Sincerely, Oleksandr. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSoC 2011 Application
Hi,
On 23 March 2011 13:49, Yuri Karadzhov yuri.karadz...@gmail.com wrote:
The first and third item would be useful to have, but they are not really
big enough projects for a summer of code. The second one could be, though.
I would need to see a more detailed plan on what you plan to implement to
see if it is big enough.
Aaron Meurer
Actually it was one idea which include three smaller ones because they
are connected with each other. The rough plan of implementation:
1. Implement pattern matching functionality. Function like Maple
indets which can return the list of subexpressions of given type from
given expression is required.
e.g. indets(f(x)+2*x+sin(y+cos(t)),'function')
should return the list
f(x), sin(y+cos(t)), cos(t)
This actually can be solved with SymPy already:
In [1]: var('t')
Out[1]: t
In [2]: (f(x)+2*x+sin(y+cos(t))).atoms(Function)
Out[2]: set(cos(t), f(x), sin(y + cos(t)))
This immediately give us the solution of the third problem (concerned
with dsolve)
2. Implement function which return minimal list of linearly
independent functions of one variable form given one.
e.g. linind(cos(t+1), sin(t), cos(t))
should return
sin(t), cos(t)
This helps to solve the first problem.
3. Then singular function should be implemented. This function should
return values of parameters which make given expression singular.
e.g. singular(tan(c)*y/(d*(a+b*x)),(a,b,c,d))
should return
(a=0, b=0),(c=Pi/2+Pi*N_1)
This is interesting. Have you looked into sympy.solvers and checked what was
already done in this direction and what more has to be done?
This helps to implement parametrizer.
4. Implement parametrizer casemap which do the require operation
parameter-wise
e.g. casemap(dsolve, diff(f(r),r)=a*f(r)+b*r+c, (a, b, c))
should return
(f(r)=C_1*exp(a*r)-b*r/a-(b+a*c)/a^2 , a!=0), (f(r)=b*r^2/2+c*r+C_1,
a=0)
the same method can be used for rank calculation using determinant
method because
A=Matrix((1, x), (1, 1))
casemap(det, Inverse(A), x)
should return
(1/(1-x), x!=1), (infinity, x=1)
This solve the second problem, but it's assumed that ODE module is
able to solve ODE's without checking of parameters. If it's not — the
improvement of ODE module should be done first.
This idea is not obligatory and if you need improvements of ODE or PDE
module or anything else, I will be glad to help.
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[sympy] GSoC Introduction. Perturbation theory
Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all sympy features, so if it possible guide me. Source: http://pygments.org/demo/16998/ P.S. Why my previous discussion(One more GSoC Introduction) was deleted? Regards, Anatolii -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] GSoC Introduction. Perturbation theory example
Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all SymPy features, so if it possible guide me. Source: http://pygments.org/demo/16998/ P.S. Why my previous discussion(One more GSoC Introduction) was deleted? Regards, Anatolii -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC Introduction. Perturbation theory
23.03.2011 19:57, weralwolf пишет: P.S. Why my previous discussion(One more GSoC Introduction) was deleted? Regards, Anatolii Is it you're talk about? http://groups.google.com/group/sympy/browse_thread/thread/3e6a1cf2c1cfd393?hl=en# I found it in: http://groups.google.com/group/sympy?hl=en Click View all near 9 of 8344 messages -- Alexey U. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] GSOC Introduction
Hello SymPy people, I’m a Computer Science student currently completing my Master’s thesis at the University of Canterbury, New Zealand. I am looking to participate in gsoc this year. I would like to contribute to sympy because I have both an interest in mathematics and Python. Python is currently my language of choice. I use Python in my studies and I also tutor Python in undergraduate classes. I’m considering the Cython project to optimise the core. I used Cython in Master’s project to optimise processor/memory intensive methods. With Cython I increase the performance of my code while leaving the original Python code unchanged by adding Cython headers (.pyx) to modules to convert the Python into C++. It would be very interesting to be involved in doing the same to sympy. Currently looking through the discussion topics to see what would be required of the Cython project. Just wanted to express my interest in this project at this moment. Ben M. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] GSOC Application
Dear list, I would like to express my interest in working no the symbolic integration capabilities of sympy as part of a GSOC project. My name is Tom Bachmann and I study mathematics (second year) at the university of cambridge, england. Here is an overview of my computer programming experience: I have previously worked on the Hurd project (in C), I did a project that started the port of the kaXen/afterburner pre-virtualisation environment to amd64 (in C++), and I have extended the wikireader codebase to handle ebooks from project gutenberg (mostly python). I can supply more details and/or references if you wish. I have also created some fun projects on my own, the most relevant here being probably what I call fz [1], a program to plot various special functions in the complex plane and on riemann surfaces (in C++). Finally here in cambridge there are so-called CATAM [2] (computer-aided teaching of all of mathematics) projects on which I got excellent results; this may or may not be meaningful to you. With this background settled, let me say that I find both of the proposed approaches to symbolic integration (resdiue theorem and Mejer functions) very interesting. I believe I do understand well the mathematics behind both. Depending on what you perceive to be more important, I would be happy to work on either, with possibly a slight preference for the residue method. What is the state of any existing implementation in sympy? If there is any specific other information that you want me to supply, please don't hesitate to let me know. Thanks, Tom [1] https://bitbucket.org/ness/fz/overview [2] http://www.maths.cam.ac.uk/undergrad/catam/ -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] GSoC 2011: Porting to Python 3
Hello, I'm a student at the Faculty of Electrical Engineering, Czech Technical University in Prague. I'm studying Open Informatics, which is a study program orientated towards research and the utilization of new technologies. While I have experience with several languages (notably C, Java, Prolog), Python is by far my favorite language. I find the issues related to conversion to Python 3 particularly interesting, and would like to work on porting SymPy to Python 3. The porting is inevitable if SymPy is to survive, and doing it sooner rather than later offers advantages that could be helpful in increased adoption (and hence increased development), so I consider it a very worthwhile pursuit. My main problem is whether this is simply big enough for a GSoC project? While it is listed on the Ideas page, after a cursory glance at the code I don't see any major problems here (or I simply missed them, of course). I have read about the last time such a conversion was attempted and the problems encountered, but as that was over 18 months ago, I believe most of those problems can be solved now. My plan would be to first run in 2.6 with no errors (ie. Python -3), which shouldn't be too difficult (around 150 errors, most of which look trivial), and then try to maintain a dual codebase with automatic running of the 2to3 tool when building for Python3 (which is the recommended procedure). Problems might arise from the fact that SymPy currently supports Python 2.4 or higher, but this would have to be solved as it comes up. I hope it will be possible to keep supporting 2.4, though limiting it to 2.6 would likely result in cleaner code. Thank you for your time, Vladimir Perić -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] GSOC 2011: Improve the plotting module
Hi Sympy Community, My name is Viktor Ikonnikov. I'm a PhD student of South Ural State University from Russia. My basic specialization is modeling and control of dynamic systems. I have a good experience of working with matplotlib, cairo, opengl and Python is my favorite language :) I want to improve the Sympy plotting module and add ability to use other plotting backends. As minimum I can integrate Sympy with matplotlib. Can I take participate in GSOC from Sympy Community with this Idea? Thanks, Viktor. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSoC Introduction. Perturbation theory
On Mar 23, 12:57 pm, weralwolf weralw...@gmail.com wrote: Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all sympy features, so if it possible guide me. Source:http://pygments.org/demo/16998/ I think you forgot to put from sympy import S at the top. Did I get it right that you calculate the ground state energy of the 1D infinite potential well of width $a$ with a perturbation which is linear in $x$, up to second order in perturbation? I think in general your code is fine. What you might want to do is - have V an operator - same for the unpertubed Hamiltonian H - being able to write those operators in matrix form in a particular basis - find the basis which diagonalizes H - use this basis to represent H and V in matrix forms - compute perturbation theory to first, second, etc. order by looking up the matrix forms - make it general enough to handle degenerate cases I think some of this is possible already, but I haven't looked deeply into it. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy][gsoc]Improving simplification
About me: Lagunov Vladimir, 21 years, living in Russia, Novosibirsk. Studying in magistracy of Novosibirsk state technical university, Faculty of Automatics and Computer Engineering. email and xmpp: lagunov.vladimir _at_ gmail.com xmpp: werehuman _at_ jabber.ru My coding skills: I prefer Python for my programs: i’m familiar with python much more than with other languages. But also i can write on C++, and i’m somewhat familiar with C, Java, JavaScript, PHP, Haskell. I worked with Django and Twisted.Web. I have no large list of big projects. My first average (more that 200 lines) program on Python was a xmpp-chat bot for quiz game, i wrote it 3 years ago. In this three years i slightly earned by improving one site based on Django and wrote a lot of small but useful scripts for myself. Or useless but funny pieces of code like http://pastebin.com/ngRaMCVQ , that i used in internet “holywars”. Now i’m writing web-interface for my master’s thesis on twisted.web. My experience doesn’t limited by Python only. My bachelor’s work was an DirectConnect client, written in Java and Swing (but this client doesn’t works as i wanted). Also i have some experience with C++ and Qt (concretely with QtGui and QtNetwork), and of course i can work with PyQt4/PySide. My task: I want to improve simplification algorithms. Somehow i just recently discover SymPy, although i needed such library has long. Nevertheless, in few days of SymPy usage, i saw that functions for expressions simplification sometimes doesn’t work as expected. Firstly i try to extend simplify() function to support more expression types. When i’ll done these task, i’ll start working on other tasks from GSoC 2011 wish list, associated with simplification. Expression simplification is an inalienable part of whole SymPy, all other components of framework are using these functional. Improving of expression simplification will affect on all parts of SymPy. I’m interested in this project for two reasons: at first i like Python, therefore i want to improve good programs on good language; at second, theme of my masters work is associated with symbolical computations. Education plan does not give me a chance to work full time 40h/week because i have an session in June and “manufacturing practice” (i will work by my specialization in some organization that i don’t know yet, this is a part of education plan in my university) in July. But there are many holidays in Russia, and also i can do something in evenings, so i think that i cope with my goal. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: Another GSoC Idea
Good to know it's already done. So it can be changed to 6. Classify algebra according to commutation relations and present the table of commutation. The other problems remain actual On Mar 23, 6:24 pm, Brian Granger elliso...@gmail.com wrote: On Wed, Mar 23, 2011 at 6:26 AM, Yuri Karadzhov yuri.karadz...@gmail.com wrote: On Mar 22, 11:31 pm, Aaron Meurer asmeu...@gmail.com wrote: I think this idea could work, but would like to see more details (anyway, there will need to be a lot more details in the application). Aaron Meurer At least it is possible to implement basic the most routine functionality 1. Generate infinitesimal operator of given variables 2. Calculate the extension of infinitesimal operator of given order 3. Calculate differential sequence of given equation (system of equations) 4. Apply the infinitesimal operator to the equation (system of equations) 5. Obtain system of determining equations 6. Calculate commutator and anticommutator of two operators For operators, commutators, etc., check out: sympy.physics.quantum.operator|commutator|anticommutator Cheers, Brian Then some additional functionality can be added 1. Obtain the classification and determining equations for the classification problem 2. If tesor module allow – implement above functionality for arbitrary order of dependent and independent variable e.g. x = (x_1,...,x_n), y =(y_1,...,y_m), where n and m is unknown 3. If PDE module allow – solve the system of determining equations 4. If above is true – completely solve the classification problem in simple cases -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email tosy...@googlegroups.com. To unsubscribe from this group, send email tosympy+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/sympy?hl=en. -- Brian E. Granger, Ph.D. Assistant Professor of Physics Cal Poly State University, San Luis Obispo bgran...@calpoly.edu elliso...@gmail.com -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Gracjan Olbinski
Hi, 2011/3/22 Gracjan Olbiński fttro...@gmail.com Hello SymPy community! Let me introduce myself. My name is Gracjan Olbinski, I'm a second year student of Computer Science and a first year of Math on Wroclaw Univeristy of Technology, Poland. I'm interested in foundation of mathematics and computer science in particular set theory and algorithmic logic. Right now I'm working on new technology of GPGPU computing which is develop by nVidia CUDA with student organisation KNSI (there is a www page but only in Polish language, you could find it at http://www.knsi.pwr.wroc.pl and http://www.knsi.pwr.wroc.pl/cuda). I am interested in participating in Sympy 2011 GSoC project. My proposals to SymPy: - *Implement symbolic (formal) logics and set theory* - *Implement definite integration algorithm using residues* (from detailed list of projects) - *Implement symbolic integration via Marichev-Adamchik Mellin transform* (this will need to made a reserach on it, so will require some more time to introduce through it before starting coding) Can you tell us more about your ideas? Formal logics and set theory are subjects that were already exploited quite a lot and SymPy has already support for this. It would be good to point out what exactly is missing and what subset of this you would like to implement. Definite integration is very weakly supported by SymPy, so this contribution would be very useful. As you want to use residues, did you check if SymPy has already a function for computing residues? If it has, maybe it needs improvements (possibly part of your project would have to be a contribution to other modules: solvers, series, etc.). Symbolic integration via G-functions (the last one) would be a very important contribution. Together with recursive Risch algorithm, that is being implemented by Aaron, this would allow SymPy to handle most integrals that can be found in the mathematical literature. I strongly suggest that you do research on this algorithm now and make sure that you realize, when writing your proposal, what has to be implemented (e.g. representation of G-functions, conversion algorithms, ...). How about my experience in Python? On course Introduction to Algorithms (similiar to MiT course by Leirserson) all programs which we had to code I wrote in python. Of course there weren't big projects e.g. B-Trees implementation + visualisation in PyQt. Programming in C and Python gives me most fun. I have learned about SymPy by GSoC list of participating Organizations, so knowledge of this library actually is not so large but in next few days I'll learn about it. Thank you. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSoC 2011 Application
Great! The pattern matching ability is the basis of any CAS. If it is done I can do a lot more on parametrization and so on. Than you for your advise, now I play around with sympy and after it I'm going to look into code more precisely. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: One more GSoC Introduction
I place example code into GSoC Introduction. Perturbation theory discussion, cause I can't view this or another discussions posted by my or anyone else after 22.03.11 -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy][gsoc]Improving simplification
Hi Vladimir, On 23 March 2011 10:38, Владимир Лагунов lagunov.vladi...@gmail.com wrote: About me: Lagunov Vladimir, 21 years, living in Russia, Novosibirsk. Studying in magistracy of Novosibirsk state technical university, Faculty of Automatics and Computer Engineering. email and xmpp: lagunov.vladimir _at_ gmail.com xmpp: werehuman _at_ jabber.ru My coding skills: I prefer Python for my programs: i’m familiar with python much more than with other languages. But also i can write on C++, and i’m somewhat familiar with C, Java, JavaScript, PHP, Haskell. I worked with Django and Twisted.Web. I have no large list of big projects. My first average (more that 200 lines) program on Python was a xmpp-chat bot for quiz game, i wrote it 3 years ago. In this three years i slightly earned by improving one site based on Django and wrote a lot of small but useful scripts for myself. Or useless but funny pieces of code like http://pastebin.com/ngRaMCVQ , that i used in internet “holywars”. Now i’m writing web-interface for my master’s thesis on twisted.web. My experience doesn’t limited by Python only. My bachelor’s work was an DirectConnect client, written in Java and Swing (but this client doesn’t works as i wanted). Also i have some experience with C++ and Qt (concretely with QtGui and QtNetwork), and of course i can work with PyQt4/PySide. Thank you for being interested in contributing to our project. Your will find information here http://asmeurersympy.wordpress.com/2011/03/18/sympy-is-a-google-summer-of-code-2011-mentoring-organization/ about GSoC application procedure. My task: I want to improve simplification algorithms. Somehow i just recently discover SymPy, although i needed such library has long. Nevertheless, in few days of SymPy usage, i saw that functions for expressions simplification sometimes doesn’t work as expected. Can you tell us more about what didn't work or worked not the way you expected it to work? Firstly i try to extend simplify() function to support more expression types. When i’ll done these task, i’ll start working on other tasks from GSoC 2011 wish list, associated with simplification. Expression simplification is an inalienable part of whole SymPy, all other components of framework are using these functional. Improving of expression simplification will affect on all parts of SymPy. Do you plan to only extend simplify() to support more classes of functions and rewrite rules, or you would like to implemented complexity measures and make this function a decision procedure for minimization of symbolic expressions (or both)? Maybe there are other areas of expression simplification you would like to explore, e.g. context based simplification, preservation of initial structure of expressions, etc. I’m interested in this project for two reasons: at first i like Python, therefore i want to improve good programs on good language; at second, theme of my masters work is associated with symbolical computations. What problems do you solve (or plan to solve) employing symbolic computations? Maybe you can share some practical examples where SymPy can be used. Education plan does not give me a chance to work full time 40h/week because i have an session in June and “manufacturing practice” (i will work by my specialization in some organization that i don’t know yet, this is a part of education plan in my university) in July. But there are many holidays in Russia, and also i can do something in evenings, so i think that i cope with my goal. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSoC Introduction. Perturbation theory
2011/3/23 Julien Rioux julien.ri...@gmail.com On Mar 23, 12:57 pm, weralwolf weralw...@gmail.com wrote: Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all sympy features, so if it possible guide me. Source:http://pygments.org/demo/16998/ I think you forgot to put from sympy import S at the top. Yes, thanks, I really miss it! I just remove it in the last moment before highlighting code. Did I get it right that you calculate the ground state energy of the 1D infinite potential well of width $a$ with a perturbation which is linear in $x$, up to second order in perturbation? Yes, you are right. I try to calculate the ground state energy for that case what you describe. I think in general your code is fine. What you might want to do is - have V an operator - same for the unpertubed Hamiltonian H - being able to write those operators in matrix form in a particular basis - find the basis which diagonalizes H - use this basis to represent H and V in matrix forms - compute perturbation theory to first, second, etc. order by looking up the matrix forms - make it general enough to handle degenerate cases I think some of this is possible already, but I haven't looked deeply into it. Thanks, I'll look deeply, may be I'll find some solutions of this points. I'll search methods to solve it in current SymPy state. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC Introduction. Perturbation theory
I don't think it's possible to delete a discussion on a public mailing list. But I think Google Groups has a bug where sometimes it does not show discussions when searching or when browsing for whatever reason. But they are still there (you can usually find them by doing a normal Google search). Aaron Meurer On Mar 23, 2011, at 10:57 AM, weralwolf wrote: Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all sympy features, so if it possible guide me. Source: http://pygments.org/demo/16998/ P.S. Why my previous discussion(One more GSoC Introduction) was deleted? Regards, Anatolii -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSOC Introduction
You might read through this thread from a few days ago http://groups.google.com/group/sympy/browse_thread/thread/18f0197965e5db61/5177840c029ea1a7. Note that there might be a problem with the Cythonizing the core because we still need to remove the old assumptions (this would itself be a whole GSoC project). However, if you are still interested in Cython, you might look at cythonizing other core parts of SymPy. Aaron Meurer On Mar 23, 2011, at 5:20 AM, Friedman wrote: Hello SymPy people, I’m a Computer Science student currently completing my Master’s thesis at the University of Canterbury, New Zealand. I am looking to participate in gsoc this year. I would like to contribute to sympy because I have both an interest in mathematics and Python. Python is currently my language of choice. I use Python in my studies and I also tutor Python in undergraduate classes. I’m considering the Cython project to optimise the core. I used Cython in Master’s project to optimise processor/memory intensive methods. With Cython I increase the performance of my code while leaving the original Python code unchanged by adding Cython headers (.pyx) to modules to convert the Python into C++. It would be very interesting to be involved in doing the same to sympy. Currently looking through the discussion topics to see what would be required of the Cython project. Just wanted to express my interest in this project at this moment. Ben M. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSOC Application
Hi. On Mar 23, 2011, at 6:43 AM, Tom Bachmann wrote: Dear list, I would like to express my interest in working no the symbolic integration capabilities of sympy as part of a GSOC project. My name is Tom Bachmann and I study mathematics (second year) at the university of cambridge, england. Here is an overview of my computer programming experience: I have previously worked on the Hurd project (in C), I did a project that started the port of the kaXen/afterburner pre-virtualisation environment to amd64 (in C++), and I have extended the wikireader codebase to handle ebooks from project gutenberg (mostly python). I can supply more details and/or references if you wish. I have also created some fun projects on my own, the most relevant here being probably what I call fz [1], a program to plot various special functions in the complex plane and on riemann surfaces (in C++). Finally here in cambridge there are so-called CATAM [2] (computer-aided teaching of all of mathematics) projects on which I got excellent results; this may or may not be meaningful to you. With this background settled, let me say that I find both of the proposed approaches to symbolic integration (resdiue theorem and Mejer functions) very interesting. I believe I do understand well the mathematics behind both. Depending on what you perceive to be more important, I would be happy to work on either, with possibly a slight preference for the residue method. What is the state of any existing implementation in sympy? If there is any specific other information that you want me to supply, please don't hesitate to let me know. Thanks, Tom [1] https://bitbucket.org/ness/fz/overview [2] http://www.maths.cam.ac.uk/undergrad/catam/ Currently, SymPy is getting pretty strong with indefinite integration, thanks to my project to implement the Risch Algorithm. However, there is really no progress with definite integration. The integrator basically uses the fundamental theorem of calculus (integrate and evaluate at the end points) to evaluate definite integrals, and that is it. So there is definitely much room for improvement in this area. Now, the Meijer G function project would be much more general (i.e., powerful) than the residue one, but I think it would also be more difficult. If you are interested in that one, you might look at the paper by Kelly Roach [1]. The residue project would probably be easier, but again, much less powerful. By the way, the integration algorithms are my particular interest in SymPy, so I would like to discuss this more with you. If you want, we can talk on IRC. Our channel is #sympy on Freenode. Finally, I want to remind you that we require all student applicants to submit at least one patch to the project that gets reviewed and pushed in. See https://github.com/sympy/sympy/wiki/development-workflow for a guide on how to submit a patch. Some easy to fix issues that can get you started are labeled EasyToFix at our issue tracker. See http://code.google.com/p/sympy/issues/list?q=label:EasyToFix. Aaron Meurer [1] - K. Roach. Meijer g function representations. In ISSAC ’97: Proceedings of the 1997 international symposium on Symbolic and algebraic computation, pages 205–211, New York, NY, USA, 1997. ACM. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Porting to Python 3
Hi. On Mar 23, 2011, at 8:31 AM, VPeric wrote: Hello, I'm a student at the Faculty of Electrical Engineering, Czech Technical University in Prague. I'm studying Open Informatics, which is a study program orientated towards research and the utilization of new technologies. While I have experience with several languages (notably C, Java, Prolog), Python is by far my favorite language. I find the issues related to conversion to Python 3 particularly interesting, and would like to work on porting SymPy to Python 3. The porting is inevitable if SymPy is to survive, and doing it sooner rather than later offers advantages that could be helpful in increased adoption (and hence increased development), so I consider it a very worthwhile pursuit. My main problem is whether this is simply big enough for a GSoC project? While it is listed on the Ideas page, after a cursory glance at the code I don't see any major problems here (or I simply missed them, of course). I have read about the last time such a conversion was attempted and the problems encountered, but as that was over 18 months ago, I believe most of those problems can be solved now. My plan would be to first run in 2.6 with no errors (ie. Python -3), which shouldn't be too difficult (around 150 errors, most of which look trivial), and then try to maintain a dual codebase with automatic running of the 2to3 tool when building for Python3 (which is the recommended procedure). Problems might arise from the fact that SymPy currently supports Python 2.4 or higher, but this would have to be solved as it comes up. I hope it will be possible to keep supporting 2.4, though limiting it to 2.6 would likely result in cleaner code. Thank you for your time, Vladimir Perić So we are planning on dropping 2.4 support after the next release (see http://code.google.com/p/sympy/issues/detail?id=2135). This should make it much easier to support Python 3 (indeed, it is already difficult to support Python 2.4 without supporting Python 3). We do plan on keeping Python 2.5 support into the future, though. Maybe others can comment on whether they think this is a suitable project or not. Previously, there were quite a few things that needed to be done for Python 3 support, but many of them have already been fixed. Definitely one thing that needs to be done is to automate as much as possible the process of handling Python 3 code. We do not want to have two separate code bases, so the best way would be if we could just code in Python 2 like we do now and have everything transferred over to Python 3 automatically. Another thing that should be considered is setting up buildbots that automatically run the tests in all versions of Python (including Python 3) to make sure everything is running OK. So I think you would have to consider a Python 3 project to be less about fixing the code base to work with Python 3 (which should not take very long), and more about making it as painless as possible for us to support it. Aaron Meurer -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSOC 2011: Improve the plotting module
Yes, fixing our plotting module is something that we need to have done. We currently ship with Pyglet, but it would be better if we modularized our plotting module to work with matplotlib, pyglet, etc. as external libraries. Just a note: to participate in GSoC, we require that you submit a patch that gets reviewed and pushed in. See https://github.com/sympy/sympy/wiki/development-workflow for a guide and http://code.google.com/p/sympy/issues/list?q=label:EasyToFix for some easy to fix issues. Aaron Meurer On Mar 23, 2011, at 11:06 AM, Viktor wrote: Hi Sympy Community, My name is Viktor Ikonnikov. I'm a PhD student of South Ural State University from Russia. My basic specialization is modeling and control of dynamic systems. I have a good experience of working with matplotlib, cairo, opengl and Python is my favorite language :) I want to improve the Sympy plotting module and add ability to use other plotting backends. As minimum I can integrate Sympy with matplotlib. Can I take participate in GSOC from Sympy Community with this Idea? Thanks, Viktor. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Porting to Python 3
Hi, On 23 March 2011 12:15, Aaron S. Meurer asmeu...@gmail.com wrote: Hi. On Mar 23, 2011, at 8:31 AM, VPeric wrote: Hello, I'm a student at the Faculty of Electrical Engineering, Czech Technical University in Prague. I'm studying Open Informatics, which is a study program orientated towards research and the utilization of new technologies. While I have experience with several languages (notably C, Java, Prolog), Python is by far my favorite language. I find the issues related to conversion to Python 3 particularly interesting, and would like to work on porting SymPy to Python 3. The porting is inevitable if SymPy is to survive, and doing it sooner rather than later offers advantages that could be helpful in increased adoption (and hence increased development), so I consider it a very worthwhile pursuit. My main problem is whether this is simply big enough for a GSoC project? While it is listed on the Ideas page, after a cursory glance at the code I don't see any major problems here (or I simply missed them, of course). I have read about the last time such a conversion was attempted and the problems encountered, but as that was over 18 months ago, I believe most of those problems can be solved now. My plan would be to first run in 2.6 with no errors (ie. Python -3), which shouldn't be too difficult (around 150 errors, most of which look trivial), and then try to maintain a dual codebase with automatic running of the 2to3 tool when building for Python3 (which is the recommended procedure). Problems might arise from the fact that SymPy currently supports Python 2.4 or higher, but this would have to be solved as it comes up. I hope it will be possible to keep supporting 2.4, though limiting it to 2.6 would likely result in cleaner code. Thank you for your time, Vladimir Perić So we are planning on dropping 2.4 support after the next release (see http://code.google.com/p/sympy/issues/detail?id=2135). This should make it much easier to support Python 3 (indeed, it is already difficult to support Python 2.4 without supporting Python 3). We do plan on keeping Python 2.5 support into the future, though. Leaving Python 2.5 support is important because Python runtime environment in Google App Engine is based on 2.5 and SymPy must run in App Engine. Maybe others can comment on whether they think this is a suitable project or not. Previously, there were quite a few things that needed to be done for Python 3 support, but many of them have already been fixed. Definitely one thing that needs to be done is to automate as much as possible the process of handling Python 3 code. We do not want to have two separate code bases, so the best way would be if we could just code in Python 2 like we do now and have everything transferred over to Python 3 automatically. Another thing that should be considered is setting up buildbots that automatically run the tests in all versions of Python (including Python 3) to make sure everything is running OK. So I think you would have to consider a Python 3 project to be less about fixing the code base to work with Python 3 (which should not take very long), and more about making it as painless as possible for us to support it. Aaron Meurer -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Gracjan Olbinski
On Mar 23, 2011, at 11:54 AM, Mateusz Paprocki wrote: Hi, 2011/3/22 Gracjan Olbiński fttro...@gmail.com Hello SymPy community! Let me introduce myself. My name is Gracjan Olbinski, I'm a second year student of Computer Science and a first year of Math on Wroclaw Univeristy of Technology, Poland. I'm interested in foundation of mathematics and computer science in particular set theory and algorithmic logic. Right now I'm working on new technology of GPGPU computing which is develop by nVidia CUDA with student organisation KNSI (there is a www page but only in Polish language, you could find it at http://www.knsi.pwr.wroc.pl and http://www.knsi.pwr.wroc.pl/cuda). I am interested in participating in Sympy 2011 GSoC project. My proposals to SymPy: • Implement symbolic (formal) logics and set theory • Implement definite integration algorithm using residues (from detailed list of projects) • Implement symbolic integration via Marichev-Adamchik Mellin transform (this will need to made a reserach on it, so will require some more time to introduce through it before starting coding) Can you tell us more about your ideas? Formal logics and set theory are subjects that were already exploited quite a lot and SymPy has already support for this. It would be good to point out what exactly is missing and what subset of this you would like to implement. Definite integration is very weakly supported by SymPy, so this contribution would be very useful. As you want to use residues, did you check if SymPy has already a function for computing residues? If it has, maybe it needs improvements (possibly part of your project would have to be a contribution to other modules: solvers, series, etc.). Symbolic integration via G-functions (the last one) would be a very important contribution. Together with recursive Risch algorithm, that is being implemented by Aaron, this would allow SymPy to handle most integrals that can be found in the mathematical literature. I strongly suggest that you do research on this algorithm now and make sure that you realize, when writing your proposal, what has to be implemented (e.g. representation of G-functions, conversion algorithms, …). By the way, a useful paper to get you started on this is [1]. Aaron Meurer [1] - K. Roach. Meijer g function representations. In ISSAC ’97: Proceedings of the 1997 international symposium on Symbolic and algebraic computation, pages 205–211, New York, NY, USA, 1997. ACM. Aaron Meurer How about my experience in Python? On course Introduction to Algorithms (similiar to MiT course by Leirserson) all programs which we had to code I wrote in python. Of course there weren't big projects e.g. B-Trees implementation + visualisation in PyQt. Programming in C and Python gives me most fun. I have learned about SymPy by GSoC list of participating Organizations, so knowledge of this library actually is not so large but in next few days I'll learn about it. Thank you. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSoC 2011 Application
On Mar 23, 2011, at 6:49 AM, Yuri Karadzhov wrote: The first and third item would be useful to have, but they are not really big enough projects for a summer of code. The second one could be, though. I would need to see a more detailed plan on what you plan to implement to see if it is big enough. Aaron Meurer Actually it was one idea which include three smaller ones because they are connected with each other. The rough plan of implementation: 1. Implement pattern matching functionality. Function like Maple indets which can return the list of subexpressions of given type from given expression is required. e.g. indets(f(x)+2*x+sin(y+cos(t)),'function') should return the list f(x), sin(y+cos(t)), cos(t) This immediately give us the solution of the third problem (concerned with dsolve) 2. Implement function which return minimal list of linearly independent functions of one variable form given one. e.g. linind(cos(t+1), sin(t), cos(t)) should return sin(t), cos(t) Do you know of an efficient algorithm to compute this? I know that it can be done, since the set is finite and the wronskian will tell you if it a set is linearly independent or not, but it seems that a naive implementation would have poor asymptotic (and actual) performance. This helps to solve the first problem. 3. Then singular function should be implemented. This function should return values of parameters which make given expression singular. e.g. singular(tan(c)*y/(d*(a+b*x)),(a,b,c,d)) should return (a=0, b=0),(c=Pi/2+Pi*N_1) This helps to implement parametrizer. 4. Implement parametrizer casemap which do the require operation parameter-wise e.g. casemap(dsolve, diff(f(r),r)=a*f(r)+b*r+c, (a, b, c)) should return (f(r)=C_1*exp(a*r)-b*r/a-(b+a*c)/a^2 , a!=0), (f(r)=b*r^2/2+c*r+C_1, a=0) the same method can be used for rank calculation using determinant method because A=Matrix((1, x), (1, 1)) casemap(det, Inverse(A), x) should return (1/(1-x), x!=1), (infinity, x=1) This could be a useful function. Probably the new assumptions could help it out (though sadly they are not fully implemented yet). Aaron Meurer This solve the second problem, but it's assumed that ODE module is able to solve ODE's without checking of parameters. If it's not — the improvement of ODE module should be done first. This idea is not obligatory and if you need improvements of ODE or PDE module or anything else, I will be glad to help. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Porting to Python 3
On Mar 23, 2011, at 1:30 PM, Mateusz Paprocki wrote: Hi, On 23 March 2011 07:31, VPeric vlada.pe...@gmail.com wrote: Hello, I'm a student at the Faculty of Electrical Engineering, Czech Technical University in Prague. I'm studying Open Informatics, which is a study program orientated towards research and the utilization of new technologies. While I have experience with several languages (notably C, Java, Prolog), Python is by far my favorite language. I find the issues related to conversion to Python 3 particularly interesting, and would like to work on porting SymPy to Python 3. The porting is inevitable if SymPy is to survive, and doing it sooner rather than later offers advantages that could be helpful in increased adoption (and hence increased development), so I consider it a very worthwhile pursuit. My main problem is whether this is simply big enough for a GSoC project? While it is listed on the Ideas page, after a cursory glance at the code I don't see any major problems here (or I simply missed them, of course). I have read about the last time such a conversion was attempted and the problems encountered, but as that was over 18 months ago, I believe most of those problems can be solved now. It's a good question whether this is big enough. Surely it's important enough to consider this as a GSoC project. I think that the biggest problem currently (unless I forgot about something else) are __cmp__ methods. We are gradually taking care of this issue across SymPy but there is still a lot of work to be done in this area. It's up to you to recognize issues that have to be fixed and figure out a schedule you would like to follow (don't hesitate to ask, because we already made some effort to make SymPy compatible with Python 3 and we have some code in development branches that could help you). If it happens that there is not enough work in porting SymPy to Python 3, then you might consider widening the project and make SymPy run in a subset of Jython, PyPy, IronPython, etc. (I don't remember which are already supported). That is also a good idea. From what I remember, that are test failures in most of these (basically because we take advantage of some feature of Python which is actually just an implementation detail from CPython). And if you set up a build system, you could also add these to it. By the way, I thought the main __cmp__ problem was the _compare_pretty function, which you have replaced in your polys12 branch. Is there some other that still remains? Aaron Meurer My plan would be to first run in 2.6 with no errors (ie. Python -3), which shouldn't be too difficult (around 150 errors, most of which look trivial), and then try to maintain a dual codebase with automatic running of the 2to3 tool when building for Python3 (which is the recommended procedure). Problems might arise from the fact that SymPy currently supports Python 2.4 or higher, but this would have to be solved as it comes up. I hope it will be possible to keep supporting 2.4, though limiting it to 2.6 would likely result in cleaner code. Thank you for your time, Vladimir Perić -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Porting to Python 3
Hi, On 23 March 2011 12:34, Aaron S. Meurer asmeu...@gmail.com wrote: On Mar 23, 2011, at 1:30 PM, Mateusz Paprocki wrote: Hi, On 23 March 2011 07:31, VPeric vlada.pe...@gmail.com wrote: Hello, I'm a student at the Faculty of Electrical Engineering, Czech Technical University in Prague. I'm studying Open Informatics, which is a study program orientated towards research and the utilization of new technologies. While I have experience with several languages (notably C, Java, Prolog), Python is by far my favorite language. I find the issues related to conversion to Python 3 particularly interesting, and would like to work on porting SymPy to Python 3. The porting is inevitable if SymPy is to survive, and doing it sooner rather than later offers advantages that could be helpful in increased adoption (and hence increased development), so I consider it a very worthwhile pursuit. My main problem is whether this is simply big enough for a GSoC project? While it is listed on the Ideas page, after a cursory glance at the code I don't see any major problems here (or I simply missed them, of course). I have read about the last time such a conversion was attempted and the problems encountered, but as that was over 18 months ago, I believe most of those problems can be solved now. It's a good question whether this is big enough. Surely it's important enough to consider this as a GSoC project. I think that the biggest problem currently (unless I forgot about something else) are __cmp__ methods. We are gradually taking care of this issue across SymPy but there is still a lot of work to be done in this area. It's up to you to recognize issues that have to be fixed and figure out a schedule you would like to follow (don't hesitate to ask, because we already made some effort to make SymPy compatible with Python 3 and we have some code in development branches that could help you). If it happens that there is not enough work in porting SymPy to Python 3, then you might consider widening the project and make SymPy run in a subset of Jython, PyPy, IronPython, etc. (I don't remember which are already supported). That is also a good idea. From what I remember, that are test failures in most of these (basically because we take advantage of some feature of Python which is actually just an implementation detail from CPython). And if you set up a build system, you could also add these to it. By the way, I thought the main __cmp__ problem was the _compare_pretty function, which you have replaced in your polys12 branch. Is there some other that still remains? It's slow and as I recall it needs improvements before we could run the whole test suite using it (though for printing is't already fine). But anyway, this is what should be a starting point for fixing __cmp__ issue. Aaron Meurer My plan would be to first run in 2.6 with no errors (ie. Python -3), which shouldn't be too difficult (around 150 errors, most of which look trivial), and then try to maintain a dual codebase with automatic running of the 2to3 tool when building for Python3 (which is the recommended procedure). Problems might arise from the fact that SymPy currently supports Python 2.4 or higher, but this would have to be solved as it comes up. I hope it will be possible to keep supporting 2.4, though limiting it to 2.6 would likely result in cleaner code. Thank you for your time, Vladimir Perić -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC Introduction. Perturbation theory example
On Wed, Mar 23, 2011 at 10:04 AM, weralwolf weralw...@gmail.com wrote: Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all SymPy features, so if it possible guide me. Source: http://pygments.org/demo/16998/ Nice! I ran your script, and got a number: -0.281647771314390 Then I printed E_n(_n, _a, _mass).n() and I got: 0.197392088021787 so the 0.197... is the original energy, and -0.281... is the corrected one? Indeed, I agree with your conclusions, it'd be really cool to make this work with brakets. P.S. Why my previous discussion(One more GSoC Introduction) was deleted? I am quite sure nobody has deleted any discussions intentionally --- is this the discussion you are referring to? https://groups.google.com/forum/#!topic/sympy/Pmoc8sHP05M Maybe google groups failed to show it temporarily? Ondrej -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy][gsoc]Improving simplification
Hello, Mateusz. Can you tell us more about what didn't work or worked not the way you expected it to work? I'll firstly looked at unittests of simplification and saw, that ratsimp() often fails. For example http://pastebin.com/yeuBa7R7 (but my improvement isn't ideal too). Also i didn't noticed yet, but at #sympy i was told, that thrigonometrical simplification is weak too. Do you plan to only extend simplify() to support more classes of functions and rewrite rules, or you would like to implemented complexity measures and make this function a decision procedure for minimization of symbolic expressions (or both)? Maybe there are other areas of expression simplification you would like to explore, e.g. context based simplification, preservation of initial structure of expressions, etc. Well, i haven't decided yet about descriptive plan of work. I can say that i want to improve sympy as much as i can. But i'll start working on quality of expressions simplification, and when i'll be satisfied, i'll pass to functional expanding. What problems do you solve (or plan to solve) employing symbolic computations? Maybe you can share some practical examples where SymPy can be used. My masters theme is about algorithms, not about appliance. But if i find such examples, i'll share. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSoC Introduction. Perturbation theory
Problem was solved when I reconnect from other network. Because before I haven't see any discussions after 22.03.11 On 23 Бер, 20:52, Aaron S. Meurer asmeu...@gmail.com wrote: I don't think it's possible to delete a discussion on a public mailing list. But I think Google Groups has a bug where sometimes it does not show discussions when searching or when browsing for whatever reason. But they are still there (you can usually find them by doing a normal Google search). Aaron Meurer On Mar 23, 2011, at 10:57 AM, weralwolf wrote: Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all sympy features, so if it possible guide me. Source:http://pygments.org/demo/16998/ P.S. Why my previous discussion(One more GSoC Introduction) was deleted? Regards, Anatolii -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Gracjan Olbinski
Thank you for your replies. Right now I'm exploring SymPy library and reading the Complex Analysis textbooks. As you said the logic and set theory is implemented with quite hight level, so firstly I want to focus on Cauchy's integral theorem and complex plain representation. As soon as I can I will remark all of my ideas. Currently I'm adding some Analytic Function and Complex Analysis Theory on my googlesite: http://sites.google.com/site/fttrobin/-gsoc-sympy. About G-functions I have been reading just few days ago when I saw it on ideas list and I thought that is something not so simple to learn but it is feasible, I think. I will not conceal that the last project is looking really hard for me and I will need lot time to introduce to it. Thank you. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Gracjan Olbinski
Indeed the Miejer G function project would be more difficult. Don't be afraid to do something simpler if you don't feel comfortable doing it. Aaron Meurer On Mar 23, 2011, at 3:48 PM, Gracjan Olbiński wrote: Thank you for your replies. Right now I'm exploring SymPy library and reading the Complex Analysis textbooks. As you said the logic and set theory is implemented with quite hight level, so firstly I want to focus on Cauchy's integral theorem and complex plain representation. As soon as I can I will remark all of my ideas. Currently I'm adding some Analytic Function and Complex Analysis Theory on my googlesite: http://sites.google.com/site/fttrobin/-gsoc-sympy. About G-functions I have been reading just few days ago when I saw it on ideas list and I thought that is something not so simple to learn but it is feasible, I think. I will not conceal that the last project is looking really hard for me and I will need lot time to introduce to it. Thank you. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Gracjan Olbinski
Hi, 2011/3/23 Gracjan Olbiński fttro...@gmail.com Thank you for your replies. Right now I'm exploring SymPy library and reading the Complex Analysis textbooks. As you said the logic and set theory is implemented with quite hight level, so firstly I want to focus on Cauchy's integral theorem and complex plain representation. As soon as I can I will remark all of my ideas. Currently I'm adding some Analytic Function and Complex Analysis Theory on my googlesite: http://sites.google.com/site/fttrobin/-gsoc-sympy. About G-functions I have been reading just few days ago when I saw it on ideas list and I thought that is something not so simple to learn but it is feasible, I think. I will not conceal that the last project is looking really hard for me and I will need lot time to introduce to it. As you are interested in definite integration, you should give G-function approach a try, at least to understand which classes of functions you will be able to cover and which not. G-functions allow to handle definite integration of very many classes of functions by just simple manipulation of G-functions's coefficients. For example here http://functions.wolfram.com/HypergeometricFunctions/MeijerG/21/02/ you will find a complete set of definite integration rules (you should be most interested in the Conditions part). The problems are: how to obtain G-function representation of an expression and how to return from G-function representation after integration to a more familiar representation (i.e. in terms of elementary, special and hypergeometric functions, if possible). In the article that Aaron suggested you will find (more or less) working solution to the later issue. For know I don't know any systematic approach to solve the former (besides pattern matching, which isn't a very systematic approach but what is used in other systems). Thank you. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. Mateusz -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSoC Introduction. Perturbation theory example
On Wed, Mar 23, 2011 at 1:42 PM, weralwolf weralw...@gmail.com wrote: On 23 Бер, 21:48, Ondrej Certik ond...@certik.cz wrote: On Wed, Mar 23, 2011 at 10:04 AM, weralwolf weralw...@gmail.com wrote: Hello, where my simple example of calculations corrections due to perturbation theory for hole with infinite walls. I thinks I didn't use all SymPy features, so if it possible guide me. Source:http://pygments.org/demo/16998/ Nice! I ran your script, and got a number: -0.281647771314390 Then I printed E_n(_n, _a, _mass).n() and I got: 0.197392088021787 so the 0.197... is the original energy, and -0.281... is the corrected one? Yes, you are right, it's exactly what I mean in script. How hard would it be to do more perturbation terms, so that we can see some kind of convergence in the energies? People don't do that by hand, because it is tedious, but with sympy, it might be possible. That'd be really cool. Indeed, I agree with your conclusions, it'd be really cool to make this work with brakets. It should be really shorter and simply. Can you guide me to get application for this idea? Definitely. Go to the wiki: https://github.com/sympy/sympy/wiki/Gsoc-current-applications and start crafting it up, then ask for feedback, and I and other people will try to help. Ondrej -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] GSoC and wiki
Hi, For those who edit wiki pages about GSoC, remarks about titles. I think that the titles of pages must be conditioned somehow. Now in https://github.com/sympy/sympy/wiki/_pages it is very hard to orient about GSoC program: ... About me: GsoC 2011 Application Geoffrey Ehrman GSoC 2011 Application by Oleksandr Gituliar Google Summer of Code 2011 Application Template Gsoc 2011 application yuri karadzhov Google Summer of Code 2011 Project Ideas GSoC 2011 Organization Application GSoC Current Applications GSoC Previous Applications ... Random Variables ... I supposed that it is because of GitHub wiki processor which automatically parse pages and extract *title of pages* (Markdawn, reStructuredText formats, but not MediaWiki format). E.g for Markdown format: # Title of Page for reStructuredText format: Title of Page And do it independently of the *page name* (bold in edit mode, that related with url of page): GsoC-2011-Application-Geoffrey-Ehrman GsoC-2011-Application-Oleksandr-Gituliar GSoC-2011-Application-Template Gsoc-2011-application-yuri-karadzhov GSoC-2011-Ideas GSoC-2011-Organization-Application Gsoc-current-applications GSoC-Previous-Applications GSoC-Proposal---Random-Variables So I offer: To use `GSoC-2011`. Neither `GsoC-2011` nor `GSoC`. with Uppercase of your name and application word, But be careful, if you change the page name (not page title) then do not forget relink it in others pages. Thanks. Alexey U. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC 2011: Gracjan Olbinski
Tommorow I'm gonna consult with my professor about G-function if he will be able to introduce me to G-functions theory (of course first I'll read and try to understand this article). I have little time to get through all of it. Oh, and I have to write this path as soon as possible. Thank you for you advices Gracjan -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Re: GSOC Introduction
Thanks for the link Aaron. What other parts of SymPy could be optimised without working on deprecated code? I could try to produce a dependence graph to find the most referenced modules. I read in that thread that removing the old assumptions could be a challenging project. What skills does it rely on? Is it more mathematics or software engineering? I have more experience in the later doing a Comp. Sc. degree (encapsulation, modularity, OO design patterns). On Mar 24, 7:56 am, Aaron S. Meurer asmeu...@gmail.com wrote: You might read through this thread from a few days agohttp://groups.google.com/group/sympy/browse_thread/thread/18f0197965e Note that there might be a problem with the Cythonizing the core because we still need to remove the old assumptions (this would itself be a whole GSoC project). However, if you are still interested in Cython, you might look at cythonizing other core parts of SymPy. Aaron Meurer On Mar 23, 2011, at 5:20 AM, Friedman wrote: Hello SymPy people, I’m a Computer Science student currently completing my Master’s thesis at the University of Canterbury, New Zealand. I am looking to participate in gsoc this year. I would like to contribute to sympy because I have both an interest in mathematics and Python. Python is currently my language of choice. I use Python in my studies and I also tutor Python in undergraduate classes. I’m considering the Cython project to optimise the core. I used Cython in Master’s project to optimise processor/memory intensive methods. With Cython I increase the performance of my code while leaving the original Python code unchanged by adding Cython headers (.pyx) to modules to convert the Python into C++. It would be very interesting to be involved in doing the same to sympy. Currently looking through the discussion topics to see what would be required of the Cython project. Just wanted to express my interest in this project at this moment. Ben M. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSOC Introduction
Le mercredi 23 mars 2011 à 16:09 -0700, Friedman a écrit : Thanks for the link Aaron. What other parts of SymPy could be optimised without working on deprecated code? I could try to produce a dependence graph to find the most referenced modules. I read in that thread that removing the old assumptions could be a challenging project. What skills does it rely on? Is it more mathematics or software engineering? I have more experience in the later doing a Comp. Sc. degree (encapsulation, modularity, OO design patterns). I think it's mostly software engineering (refactoring, interface design, ...) with a side dish of hardcore CS/AI topics (knowledge base maintenance and indexing, inductive reasoning, ...) We probably also need to implement simplification of boolean expressions. On Mar 24, 7:56 am, Aaron S. Meurer asmeu...@gmail.com wrote: You might read through this thread from a few days agohttp://groups.google.com/group/sympy/browse_thread/thread/18f0197965e Note that there might be a problem with the Cythonizing the core because we still need to remove the old assumptions (this would itself be a whole GSoC project). However, if you are still interested in Cython, you might look at cythonizing other core parts of SymPy. Aaron Meurer On Mar 23, 2011, at 5:20 AM, Friedman wrote: Hello SymPy people, I’m a Computer Science student currently completing my Master’s thesis at the University of Canterbury, New Zealand. I am looking to participate in gsoc this year. I would like to contribute to sympy because I have both an interest in mathematics and Python. Python is currently my language of choice. I use Python in my studies and I also tutor Python in undergraduate classes. I’m considering the Cython project to optimise the core. I used Cython in Master’s project to optimise processor/memory intensive methods. With Cython I increase the performance of my code while leaving the original Python code unchanged by adding Cython headers (.pyx) to modules to convert the Python into C++. It would be very interesting to be involved in doing the same to sympy. Currently looking through the discussion topics to see what would be required of the Cython project. Just wanted to express my interest in this project at this moment. Ben M. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] GSoC and wiki
On Mar 23, 2011, at 4:25 PM, Alexey U. Gudchenko wrote: Hi, For those who edit wiki pages about GSoC, remarks about titles. I think that the titles of pages must be conditioned somehow. Now in https://github.com/sympy/sympy/wiki/_pages it is very hard to orient about GSoC program: ... About me: GsoC 2011 Application Geoffrey Ehrman GSoC 2011 Application by Oleksandr Gituliar Google Summer of Code 2011 Application Template Gsoc 2011 application yuri karadzhov Google Summer of Code 2011 Project Ideas GSoC 2011 Organization Application GSoC Current Applications GSoC Previous Applications ... Random Variables ... I supposed that it is because of GitHub wiki processor which automatically parse pages and extract *title of pages* (Markdawn, reStructuredText formats, but not MediaWiki format). Does it? I though it asked your for the page name when you create a new page? E.g for Markdown format: # Title of Page for reStructuredText format: Title of Page And do it independently of the *page name* (bold in edit mode, that related with url of page): GsoC-2011-Application-Geoffrey-Ehrman GsoC-2011-Application-Oleksandr-Gituliar GSoC-2011-Application-Template Gsoc-2011-application-yuri-karadzhov GSoC-2011-Ideas GSoC-2011-Organization-Application Gsoc-current-applications GSoC-Previous-Applications GSoC-Proposal---Random-Variables So I offer: To use `GSoC-2011`. Neither `GsoC-2011` nor `GSoC`. with Uppercase of your name and application word, Yes, let's use this convention. Title the page like GSoC 2011 Application Your Name. Someone go ahead and rename all existing pages to this format. Aaron Meurer But be careful, if you change the page name (not page title) then do not forget relink it in others pages. Thanks. Alexey U. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Re: GSOC Introduction
Yes, maybe you could look at cythonizing the logic code (ilke the SAT solver). Another idea that comes to mind is the matrices. The other really big main part aside from the core is the polys, but Mateusz has already been working on cythonizing the core of that. Maybe you could see what he has done and if more could be done (see the @cythonized decorators in some of the files in sympy/polys/). Aaron Meurer On Mar 23, 2011, at 5:44 PM, Ronan Lamy wrote: Le mercredi 23 mars 2011 à 16:09 -0700, Friedman a écrit : Thanks for the link Aaron. What other parts of SymPy could be optimised without working on deprecated code? I could try to produce a dependence graph to find the most referenced modules. I read in that thread that removing the old assumptions could be a challenging project. What skills does it rely on? Is it more mathematics or software engineering? I have more experience in the later doing a Comp. Sc. degree (encapsulation, modularity, OO design patterns). I think it's mostly software engineering (refactoring, interface design, ...) with a side dish of hardcore CS/AI topics (knowledge base maintenance and indexing, inductive reasoning, ...) We probably also need to implement simplification of boolean expressions. On Mar 24, 7:56 am, Aaron S. Meurer asmeu...@gmail.com wrote: You might read through this thread from a few days agohttp://groups.google.com/group/sympy/browse_thread/thread/18f0197965e Note that there might be a problem with the Cythonizing the core because we still need to remove the old assumptions (this would itself be a whole GSoC project). However, if you are still interested in Cython, you might look at cythonizing other core parts of SymPy. Aaron Meurer On Mar 23, 2011, at 5:20 AM, Friedman wrote: Hello SymPy people, I’m a Computer Science student currently completing my Master’s thesis at the University of Canterbury, New Zealand. I am looking to participate in gsoc this year. I would like to contribute to sympy because I have both an interest in mathematics and Python. Python is currently my language of choice. I use Python in my studies and I also tutor Python in undergraduate classes. I’m considering the Cython project to optimise the core. I used Cython in Master’s project to optimise processor/memory intensive methods. With Cython I increase the performance of my code while leaving the original Python code unchanged by adding Cython headers (.pyx) to modules to convert the Python into C++. It would be very interesting to be involved in doing the same to sympy. Currently looking through the discussion topics to see what would be required of the Cython project. Just wanted to express my interest in this project at this moment. Ben M. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group athttp://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] Test failures in sympy master
Hello everyone, I just forked the git repository for the first time and ran setup.py test in order to make sure everything was working fine on my system before I started changing things. Unfortunately, I seem to have gotten a couple of errors that I do not quite understand, and I was hoping that someone on the list could help me. These tests are run with Python 2.5.2. Note that I haven't actually changed anything yet...this is just me trying to test my forked version of the master. xpassed tests _ sympy/simplify/tests/test_sqrtdenest.py: __ /home/lazovich/sympy/sympy/utilities/tests/test_codegen.py __ File /home/lazovich/sympy/sympy/utilities/tests/test_codegen.py, line 1063 except CodeGenError as e: ^ SyntaxError: invalid syntax __ sympy/solvers/tests/test_solvers.py:test_tsolve_1 ___ File /home/lazovich/sympy/sympy/solvers/tests/test_solvers.py, line 231, in test_tsolve_1 [-((4*log(7) + 5*LambertW(-7*2**Rational(4,5)*6**Rational(1,5)*log(7)/10))/(3*log(7)))]] AssertionError Any help is greatly appreciated! Thanks! Tomo Lazovich -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
Re: [sympy] Test failures in sympy master
Le mercredi 23 mars 2011 à 21:38 -0400, Tomo Lazovich a écrit : Hello everyone, I just forked the git repository for the first time and ran setup.py test in order to make sure everything was working fine on my system before I started changing things. Unfortunately, I seem to have gotten a couple of errors that I do not quite understand, and I was hoping that someone on the list could help me. These tests are run with Python 2.5.2. Note that I haven't actually changed anything yet...this is just me trying to test my forked version of the master. You don't have any actual problems. We've just been remiss in our testing of different platforms and Python versions. We really need to get buildbot or similar back up again. Please ignore these errors for now. xpassed tests _ sympy/simplify/tests/test_sqrtdenest.py: This says that a test that's known to fail in some cases passes for you. __ /home/lazovich/sympy/sympy/utilities/tests/test_codegen.py __ File /home/lazovich/sympy/sympy/utilities/tests/test_codegen.py, line 1063 except CodeGenError as e: ^ SyntaxError: invalid syntax This is a bug in the test file. That syntax is only valid starting from 2.6, but we want to support 2.4+. __ sympy/solvers/tests/test_solvers.py:test_tsolve_1 ___ File /home/lazovich/sympy/sympy/solvers/tests/test_solvers.py, line 231, in test_tsolve_1 [-((4*log(7) + 5*LambertW(-7*2**Rational(4,5)*6**Rational(1,5)*log(7)/10))/(3*log(7)))]] AssertionError Actually, I just reported that one: http://code.google.com/p/sympy/issues/detail?id=2226 Any help is greatly appreciated! Thanks! Tomo Lazovich -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy +unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en. -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] One more GSoC idea
Hi, I'm developing an Python packages for solving stochastic differential equations (SDE's). Both solvers for symbolic and numeric (scitools) are included. The sources are available from http://diffusion.cgu.edu.tw/ftp/sde test.py sde,py Fey-kac.gif (simulation) Could this package be added to the idea? Best regards, chu-ching huang cchuang2...@mail.com Math Group, CGE Chang-Gung University, Taiwan -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
[sympy] More GSoC Ideas
Hi, I've been thinking about GSoC and looking at the various ideas people have been posting. By the way, I'd like to see perturbation theory included in general (i.e., not just for quantum mechanics) since it's used in stability analysis. I have a few linear algebra related ideas I'd like to see. One is abstract linear algebra. That is support for arbitrary matrix and vector calculations. So, one would just indicate that a symbol is a matrix/vector without stating the size. Then you could work with them. The non-commutative support is a start, but the transpose operation would need to be added along with derivatives. I have a Maple worksheet that has a crude version of this. This is used quite a bit in the Ritz approach to Finite Element Analysis. The other linear algebra thing to add is support for block matrices. So, one could specify a matrix like M = [[A,B],[C,D]] where A, B, C, and D are arbitrary matrices. Then, you could take the inverse and other standard linear algebra. This fits in with the abstract linear algebra support. This kind of thing pops up a lot in control theory. Cheers, Tim. --- Tim Lahey PhD Candidate, Systems Design Engineering University of Waterloo http://about.me/tjlahey -- You received this message because you are subscribed to the Google Groups sympy group. To post to this group, send email to sympy@googlegroups.com. To unsubscribe from this group, send email to sympy+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
