Hi Simon, On Mon, 25 Oct 2010 06:09:16 -0700 (PDT) Simon King <[email protected]> wrote:
> On 25 Okt., 14:39, Burcin Erocal <[email protected]> wrote: > > If we return an identity operator for these cases, how do you plan > > to test for it in your code: > > Something like this: > > L = x.operands() > if len(L)>1: > return x.operator()(*map(lambda ..., L)) > else: > try: > return x.operator()(round(L[0],...)) > except TypeError: > return x This initializes a list with a single element for objects which return None for operator() now. IMHO, this approach is inefficient. In this case, you should act on the object directly. In any case, we should wrap the following ginac interfaces to provide a better way of doing this: * A way to apply a function to the operands of an expression: http://www.ginac.de/tutorial/Applying-a-function-on-subexpressions.html * or tree traversal: http://www.ginac.de/tutorial/Visitors-and-tree-traversal.html Cheers, Burcin -- 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/sage-support URL: http://www.sagemath.org
