Never mind, I figured this out myself: On Mon, Nov 10, 2008 at 1:15 PM, Brian Granger <[EMAIL PROTECTED]> wrote: > OK, sounds great. Now a follow on....or two... > > * How can I get the non-commuting part of the Mul? I see that > Mul.flatten knows about it, but I don't see how to get it back.
Just do Mul.flatten(o.args) where o is my Mul instance > * I then need to take an expression, find all the instances of Mul in > the tree and replace those by something else, one by one. Is there a > simple way of doing this? the most common usage case that I will have > is a sum of terms; Use o.atoms(Mul) to get a set of all the Mul instances and then use o.subs(old, new) to rewrite them all. Having fun now... Brian > 3*A*B*|state1> + 4*C*D*|state> > > Thanks!!! > > Brian > > On Mon, Nov 10, 2008 at 1:08 PM, Ondrej Certik <[EMAIL PROTECTED]> wrote: >> >> On Mon, Nov 10, 2008 at 9:57 PM, Brian Granger <[EMAIL PROTECTED]> wrote: >>> >>> This is what I was afraid of. The problem is that the __mul__ that I >>> need to get rid of is on Basic, which all my classes inherit from. I >>> will probably just write a function that takes the flattened args of >>> the final Mul class and "do the right thing" >> >> Exactly, that's the way to go, because we want to be able to >> manipulate with the state in this form as well: >> >> A*B*C*D*|n> >> >> and optionally convert it to the form: >> >> E*|m> >> >> So the only way is to let sympy handle the multiplication (i.e. >> associative but not commutative) and then apply our own function to >> actually simplify it. >> >> Ondrej >> >> >> >> > --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
