He all, I've read the posts. And the tutorial. And the code.
Still I'm having trouble defining my own functions. Let's start with the very basics: I would like to define f(x) = 2 * x: from sympy import * from sympy.abc import x, y import sympy class Double(Function): u"""A simple function that doubles the input.""" @classmethod def eval(cls, arg): return None def fdiff(self, argindex = 1): return Integer(2) * self.args[0] def __new__(cls, *args, **kwargs): return super(Double, cls).__new__(cls, *args, **kwargs) def __init__(self, *args, **kwargs): super(Double, self).__init__() d = Double('d') d(2) When I run the code I get: TypeError: 'Double' object is not callable How can I pythonically/sympythonically define a Double inheriting from function? Notice that this is just a first step in defining more 'complex' functions (so don't tell me to use Lambda). Grea work with the project! Thank you! -- 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+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at https://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/7cdffc27-8187-43af-a6be-68b15fbe9197%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.