Okay, I'll start on that once I manage to get the integration algorithm to handle most problems that a high-school/freshman college student would encounter. (Currently it won't handle any trig integrands involving more than a u-substitution, and does not use integration by parts.)
Perhaps the derivative implementation doesn't need to be in SymPy? I haven't seen a case yet where it provides a better result (usually it is less simplified, especially when trigonometry is involved). On Saturday, March 16, 2013 7:57:12 PM UTC-7, Aaron Meurer wrote: > > This is something SymPy wants. It's even on the GSoC ideas list. > > I would put the integration stuff in the integration module. As I > pointed out on the pull request, what you really have here is a new > integration heuristic, which can (should) be "integrated" with > integrate() itself. It is already giving better results than > integrate() for some integrals (namely the one you posted as your > example). > > The diff code I'm not sure. I guess it could go in the same file for > now. If you derive the rules automatically, then the code will be > short (it will only consist of special cases like Add and Mul). > > In general, there are a lot of things that this could be applied to > beyond diff() and integrate(): solve(), simplify(), the core (like x + > x => 2*x). For some, the code could naturally live very close to the > code that currently does the work. For others, the way that the > algorithm works and the way it works "by hand" are much different. > > To be clear, the symbolic manipulation should go in SymPy. The part > about the text "now make the u substitution u = exp(x)" or the css > formatting should go in SymPy Gamma. The SymPy objects should be easy > to parse into those things, but they should be intended for machine > consumption more than human consumption. > > Aaron Meurer > > On Sat, Mar 16, 2013 at 8:47 PM, David Li <li.da...@gmail.com<javascript:>> > wrote: > > Alright, thank you for pointing out that typo. I've fixed it. > > > > I have finished porting; the code is still at the same place, > > https://github.com/sympy/sympy_gamma/pull/8. If this is something SymPy > > would want, how best should be integrated? Which module(s) does it > belong in > > and what should the API be? > > > > On Saturday, March 16, 2013 6:34:22 AM UTC-7, Ramana Venkata wrote: > >> > >> Hi David, > >> > >> Great work. Just wanted to point you out one small thing in > >> > http://sympy-gamma-li.appspot.com/input/?i=integrate%28exp%28x%29%20/%20%281%20%2B%20exp%282x%29%29%29 > > >> In the first step after "Let u = e^x"; "then let du = e^x ..." But I > think > >> it be some thing like this "then du = e^x dx ..." > >> > >> > >> On Thursday, March 14, 2013 8:52:25 PM UTC+5:30, David Li wrote: > >>> > >>> Hello all, > >>> > >>> I have implemented a module giving steps for most derivatives and some > >>> integrals for SymPy Gamma. However, it was suggested that at least > some of > >>> this functionality should be added to SymPy itself. If so, what > >>> functionality should be added and how should it be integrated into > SymPy? > >>> > >>> The pull request is at https://github.com/sympy/sympy_gamma/pull/8. > There > >>> is still some work left to do, which is listed in the pull request. In > >>> particular, integral forms involving the application of trigonometric > >>> identities need to be implemented. > >>> > >>> Examples: > >>> > >>> Integral involving arctangent and exponentiation: > >>> > http://sympy-gamma-li.appspot.com/input/?i=integrate%28exp%28x%29%20/%20%281%20%2B%20exp%282x%29%29%29 > > >>> Trig integral involving u-substitution: > >>> > http://sympy-gamma-li.appspot.com/input/?i=integrate%28sin%28sin+x%29cos+x%29 > >>> Trig derivative: > >>> http://sympy-gamma-li.appspot.com/input/?i=diff%28cot+sin+x%29 > >>> > >>> Implementation: > >>> > >>> The module builds a tree of rules to apply, with the first rule on the > >>> top of the tree. Examples of rules would be AddRule, ChainRule, > RewriteRule, > >>> AlternativeRule (in case multiple methods exist), and so on. Separate > >>> functions apply the rules and return the resulting derivative or > integral > >>> (currently derivatives and integrals are separate functions). A set of > >>> classes walks the tree and generates steps for the rules; there is no > >>> translation support but multiple output formats should work (currently > only > >>> plaintext and HTML+LaTeX are implemented). > >>> > >>> The code makes use of context managers, which would need to be > replaced > >>> in order to maintain Python 2.5 compatibility. > >>> > >>> Thank you, > >>> David Li > > > > -- > > You received this message because you are subscribed to the Google > Groups > > "sympy" group. > > To unsubscribe from this group and stop receiving emails from it, send > an > > email to sympy+un...@googlegroups.com <javascript:>. > > To post to this group, send email to sy...@googlegroups.com<javascript:>. > > > Visit this group at http://groups.google.com/group/sympy?hl=en. > > For more options, visit https://groups.google.com/groups/opt_out. > > > > > -- You received this message because you are subscribed to the Google Groups "sympy" group. 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