It used to do this and it caused a lot of problems. See http://code.google.com/p/sympy/issues/detail?id=2049 and the issues referenced there.
Aaron Meurer On Jun 20, 2012, at 4:24 PM, "[email protected]" <[email protected]> wrote: > At least in the following situation it makes sense: > > In [6]: a = Subs(Derivative(g(x, y), y), (y,), (t**2,)) > > In [7]: a.subs(g, Lambda([x,y], x*y)) > Out[7]: Subs(Derivative(_y*x, _y), (_y,), (t**2,)) > > In [8]: a.subs(g, Lambda([x,y], x*y)).doit() > Out[8]: x > > What do you think? > > -- > 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.
