> sage: f = x*y > sage: f(3,2) > 6 > sage: f(3) > 3*y > sage: f(x,2) > 2*x > sage: f(x=3) > 3*y > sage: f(y=2) > 2*x
>From what I saw, in the code f(x,2) is already supported, but it means replace x with 2, so the above syntax would interfere with the current implementation. Even f(3,2) is supported. It looks for 3 and replaces it with 2. However, I support the syntax suggested above. It would just require a change to the current syntax. If the variable names are not passed in explicitly, it seems like it would be convenient to be able to choose the ordering of the dependent variables. For example, you might have the equation: f = a*x + b*y Suppose you want to treat a and b as parameters and x and y and the fundamental function variables. In this case it would be convenient to be able to do f(3,2) and have it know you want f(x=2,y=2) rather than f (a=3,b=2). This would be possible if there were a way to define the lexigraphical ordering (there must be some code for lexigraphical ordering since groebner bases are included - I'm curious whether the code would be useful here). In addition, if an implicit syntax is included (where variable names are not passed in explicitly), it would seem to be useful to have a function that printed out the order of dependence (for reference). I know there is an 'atoms' function now that returns the set of variables used in an expression. Maybe this could be modified to include an 'ordered' argument that returns a list of items in the lexigraphical order: f.atoms(ordered=True) Output > [x,y,a,b] -Lance --~--~---------~--~----~------------~-------~--~----~ 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 [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---
