I'm not sure about that. Doesn't that assume that a lambda expression is going to return a floating point (or at least numeric) value?
Aaron Meurer On Thu, Feb 9, 2012 at 1:58 PM, [email protected] <[email protected]> wrote: > On 9 February 2012 21:39, Aaron Meurer <[email protected]> wrote: >> I'm assuming you answered your own questions here with your symbolic >> nsolve. Were there any issues that you didn't resolve? > > Just one issue: the sympification of lambda x : x > > Does it make sense for sympify(lambda x : x) to return an > implemented_function with an _imp = lambda x: x? > > Otherwise the nsolve stuff is dealt with in the pull request for > symbolic nsolve. > >> >> Aaron Meurer >> >> On Tue, Jan 10, 2012 at 9:34 AM, [email protected] >> <[email protected]> wrote: >>> The problem of "python functions evaluate immediately sympy functions don't" >>> is obvious when one tries to plot/lambdify something that contains both Expr >>> and some numerical routine. Try to imagine a way to plot >>> nsolve(..)*some_Expr for example. >>> >>> On 10 January 2012 17:30, [email protected] >>> <[email protected]> wrote: >>>> >>>> Or more likely it's better to use implemented_function that is imported >>>> from utilities.lambdify? >>>> It seems to me that implemented_function is quite important if one wants >>>> for example to have complicated numerical routines accessible as sympy >>>> expressions. In my opinion it's actually important enough to be mentioned >>>> in >>>> the tutorial/pitfalls. Because defining a function to be used in sympy is >>>> actually not as simple as defining a python function (python functions >>>> evaluate immediately, sympy functions do not). >>>> >>>> Another question that I need help with is what is Lambda used for. Is >>>> there something that Lambda does and implemented_function does not? >>>> >>>> >>>> On 10 January 2012 16:39, [email protected] >>>> <[email protected]> wrote: >>>>> >>>>> How can I represent an unevaluated call to nsolve as a sympy expression? >>>>> Is Lambda the best (and standard) solution? >>>>> >>>>> The expression I want to represent looks like nsolve(x-tanh(x-h),[x],0). >>>>> The free symbol is h. It's in the context of plotting phase transition >>>>> diagrams. >>>> >>>> >>> >>> -- >>> You received this message because you are subscribed to the Google Groups >>> "sympy" group. >>> To post to this group, send email to [email protected]. >>> To unsubscribe from this group, send email to >>> [email protected]. >>> 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 [email protected]. >> To unsubscribe from this group, send email to >> [email protected]. >> 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 [email protected]. > To unsubscribe from this group, send email to > [email protected]. > 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 [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
