Here is a simpler example of the behavior I would like: (2) variables x,y,z (3) e1 = x*(y+z)^.5 -> (4) e1 = x*(y+z)^0.5
(5) e2 = x*y*(y+z)^0.5 -> (6) e2 = x*y*(y+z)^0.5 (7) e1+e2 Result = x*(1+y)*(y+z)^0.5 (7) In the simplest case of an Add with two terms, it seems like if: 1) Both Add terms (a1 and a2, say) are Mul instances and (set(a1.args) & set(a2.args)) != set([]) or 2) One Mul (a1) and one Symbol (a2) and (set(a1.args) & set(a2)) != set([]) then they have common factors and could be combined. Any thoughts? ~Luke On Aug 14, 9:49 pm, Luke <hazelnu...@gmail.com> wrote: > I am trying to get the following two expressions to combine under addition: > e1 = rf*(1 - (c5*s2 + c2*s4*s5)**2)**(-0.5) > e2 = rf*(-c5*s2 - c2*s4*s5)*(1 - (c5*s2 + c2*s4*s5)**2)**(-0.5) > > Is there a way to make the add combine these to obtain the result: > rf*(1 - (c5*s2 + c2*s4*s5))*(1 - (c5*s2 + c2*s4*s5))**(-0.5) > > which would automatically simpify even further to: > rf*(1 - (c5*s2 + c2*s4*s5))**(0.5) > > It seems like this could be made automatic if Add could look at the > hash of each of the arguments of its arguments, and if any of them > were equal, they could be made to combine 'automatically'. > > It is interesting that Mul can auto combine things like: rf*(1 - > (c5*s2 + c2*s4*s5))*(1 - (c5*s2 + c2*s4*s5))**(-0.5), but Add does > not. > > Would this be hard to implement in Add? > > Thanks, > ~Luke --~--~---------~--~----~------------~-------~--~----~ 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 sympy+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---
