Le mercredi 12 octobre 2022 à 01:47:31 UTC+2, asme...@gmail.com a écrit :
> Can you open an issue in the issue tracker for this > https://github.com/sympy/sympy/issues/new. Done. <https://github.com/sympy/sympy/issues/24135> HTH, > It looks like it is getting > stuck trying to compute polynomial gcds. The issue seems to be > specific to I. If you instead replace J with a real number, it works. > My guess is the fact that it's an algebraic extension causes it to get > stuck in some slow polys algorithm, or possibly an algorithm that is > bugged. > > Aaron Meurer > > On Tue, Oct 11, 2022 at 4:41 AM emanuel.c...@gmail.com > <emanuel.c...@gmail.com> wrote: > > > > Consider : > > > > from sympy import symbols, Eq, solve, I > > L1, L2, L3, L4, C1, C2, C3, C4, M23, I1, I2, I3, I4, U, w, p, RL, J = \ > > symbols("L1, L2, L3, L4, C1, C2, C3, C4, M23, I1, I2, I3, I4, U, w, p, > RL, J") > > Sys = [Eq(I1*(J*L1*w - J/(C1*w)) + I2*J/(C1*w), U), > > Eq(I2*(J*L2*w - J/(C2*w) - J/(C1*w)) + I3*(J*M23*w + J/(C2*w)) + > I1*J/(C1*w), 0), > > Eq(I2*(J*M23*w + J/(C2*w)) + I3*(J*L3*w - J/(C3*w) - J/(C2*w)) + > I4*J/(C3*w), 0), > > Eq(I4*RL + I3*J/(C3*w) - I4*J/(C3*w), 0)] > > IVars = [I1, I2, I3, I4] > > Sol = solve(Sys, IVars) > > Chk = [u.subs(Sol).simplify() for u in Sys] > > > > This system is solved in a matter of milliseconds, and the (unique) > solution is correct : > > > > >>> Chk [True, True, True, True] > > > > However, this : > > > > >>> Sys0 = [u.subs({J:I}) for u in Sys] > > >>> Sol0 = solve(Sys0, IVars) > > > > “never” returns (i. e. didn’t return after >90 minutes). > > > > WTF ? > > > > -- > > You received this message because you are subscribed to the Google > Groups "sympy" group. > > To unsubscribe from this group and stop receiving emails from it, send > an email to sympy+un...@googlegroups.com. > > To view this discussion on the web visit > https://groups.google.com/d/msgid/sympy/fb2649d3-cba4-4919-bd05-d9de178bb561n%40googlegroups.com. > > > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/2df74aab-9930-403e-9831-58f30747180dn%40googlegroups.com.