The general approach for computing series in SymPy is algorithmically misdesigned.
See: https://github.com/sympy/sympy/issues/26957 On Thu, 22 Aug 2024 at 13:26, emanuel.c...@gmail.com <emanuel.charpent...@gmail.com> wrote: > > The series method of a (large) expressin doesn’t return : > > from sympy import * x1, x2, x3, x4, w1, w2, w3, w4, w5, w5, w6 = symbols("x1, > x2, x3, x4, w1, w2, w3, w4, w5, w5, w6") g= > 1/4*((w1**2*w3**2*x1**4*x2**6*x3**8 + 2*(w1**2*w3**2*x1**4*x2**6 + > w1**2*w3*x1**3*x2**5)*x3**7 + (w1**2*w3**2*x1**4*x2**6 + > 2*w1**2*w3*x1**3*x2**5 + 2*w1**2*x1**2*x2**4)*x3**6)*x4**6 + > 2*((w1**2*w3**2*x1**4*x2**6 + (w1**2*w3**2*x1**4 + (2*w1**2*w3 + > w1*w3**2)*x1**3)*x2**5)*x3**7 + 2*(w1**2*w3**2*x1**4*x2**6 + > (w1**2*w3**2*x1**4 + (3*w1**2*w3 + w1*w3**2)*x1**3)*x2**5 + (w1**2*w3*x1**3 + > (w1**2 + w1*w3)*x1**2)*x2**4)*x3**6 + (w1**2*w3**2*x1**4*x2**6 + > (w1**2*w3**2*x1**4 + (4*w1**2*w3 + w1*w3**2)*x1**3)*x2**5 + 2*(w1**2*w3*x1**3 > + (2*w1**2 + w1*w3)*x1**2)*x2**4 + 2*(w1**2*x1**2 + > w1*x1)*x2**3)*x3**5)*x4**5 + ((w1**2*w3**2*x1**4*x2**6 + 2*(w1**2*w3**2*x1**4 > + (3*w1**2*w3 + 2*w1*w3**2)*x1**3)*x2**5 + (w1**2*w3**2*x1**4 + 2*(3*w1**2*w3 > + 2*w1*w3**2)*x1**3 + 2*(3*w1**2 + 6*w1*w3 + w3**2)*x1**2)*x2**4)*x3**6 + > 2*(w1**2*w3**2*x1**4*x2**6 + (2*w1**2*w3**2*x1**4 + (7*w1**2*w3 + > 4*w1*w3**2)*x1**3)*x2**5 + (w1**2*w3**2*x1**4 + 4*(2*w1**2*w3 + > w1*w3**2)*x1**3 + (9*w1**2 + 16*w1*w3 + 2*w3**2)*x1**2)*x2**4 + > (w1**2*w3*x1**3 + (3*w1**2 + 4*w1*w3)*x1**2 + 2*(3*w1 + w3)*x1)*x2**3)*x3**5 > + (w1**2*w3**2*x1**4*x2**6 + 2*(w1**2*w3**2*x1**4 + 2*(2*w1**2*w3 + > w1*w3**2)*x1**3)*x2**5 + (w1**2*w3**2*x1**4 + 2*(5*w1**2*w3 + > 2*w1*w3**2)*x1**3 + 2*(7*w1**2 + 10*w1*w3 + w3**2)*x1**2)*x2**4 + > 2*(w1**2*w3*x1**3 + (5*w1**2 + 4*w1*w3)*x1**2 + 2*(5*w1 + w3)*x1)*x2**3 + > 2*(w1**2*x1**2 + 4*w1*x1 + 2)*x2**2)*x3**4)*x4**4 + 2*(((w1**2*w3 + > w1*w3**2)*x1**3*x2**5 + (2*(w1**2*w3 + w1*w3**2)*x1**3 + (3*w1**2 + 10*w1*w3 > + 2*w3**2)*x1**2)*x2**4 + ((w1**2*w3 + w1*w3**2)*x1**3 + (3*w1**2 + 10*w1*w3 > + 2*w3**2)*x1**2 + 4*(3*w1 + 2*w3)*x1)*x2**3)*x3**5 + (2*(w1**2*w3 + > w1*w3**2)*x1**3*x2**5 + (4*(w1**2*w3 + w1*w3**2)*x1**3 + (7*w1**2 + 22*w1*w3 > + 4*w3**2)*x1**2)*x2**4 + 2*((w1**2*w3 + w1*w3**2)*x1**3 + 2*(2*w1**2 + > 6*w1*w3 + w3**2)*x1**2 + (17*w1 + 10*w3)*x1)*x2**3 + ((w1**2 + 2*w1*w3)*x1**2 > + 2*(5*w1 + 2*w3)*x1 + 8)*x2**2)*x3**4 + ((w1**2*w3 + w1*w3**2)*x1**3*x2**5 + > 2*((w1**2*w3 + w1*w3**2)*x1**3 + (2*w1**2 + 6*w1*w3 + w3**2)*x1**2)*x2**4 + > ((w1**2*w3 + w1*w3**2)*x1**3 + (5*w1**2 + 14*w1*w3 + 2*w3**2)*x1**2 + > 12*(2*w1 + w3)*x1)*x2**3 + ((w1**2 + 2*w1*w3)*x1**2 + 2*(7*w1 + 2*w3)*x1 + > 12)*x2**2 + 2*(w1*x1 + 2)*x2)*x3**3)*x4**3 + 24*(x2**2 + 2*x2 + 1)*x3**2 + > 2*(((w1**2 + 4*w1*w3 + w3**2)*x1**2*x2**4 + 2*((w1**2 + 4*w1*w3 + > w3**2)*x1**2 + (8*w1 + 7*w3)*x1)*x2**3 + ((w1**2 + 4*w1*w3 + w3**2)*x1**2 + > 2*(8*w1 + 7*w3)*x1 + 20)*x2**2)*x3**4 + 2*((w1**2 + 4*w1*w3 + > w3**2)*x1**2*x2**4 + (2*(w1**2 + 4*w1*w3 + w3**2)*x1**2 + 3*(6*w1 + > 5*w3)*x1)*x2**3 + ((w1**2 + 4*w1*w3 + w3**2)*x1**2 + 4*(5*w1 + 4*w3)*x1 + > 27)*x2**2 + ((2*w1 + w3)*x1 + 7)*x2)*x3**3 + ((w1**2 + 4*w1*w3 + > w3**2)*x1**2*x2**4 + 2*((w1**2 + 4*w1*w3 + w3**2)*x1**2 + 2*(5*w1 + > 4*w3)*x1)*x2**3 + ((w1**2 + 4*w1*w3 + w3**2)*x1**2 + 6*(4*w1 + 3*w3)*x1 + > 36)*x2**2 + 2*((2*w1 + w3)*x1 + 9)*x2 + 2)*x3**2)*x4**2 + 24*x2**2 + > 48*(x2**2 + 2*x2 + 1)*x3 + 12*(((w1 + w3)*x1*x2**3 + (2*(w1 + w3)*x1 + > 5)*x2**2 + ((w1 + w3)*x1 + 5)*x2)*x3**3 + (2*(w1 + w3)*x1*x2**3 + (4*(w1 + > w3)*x1 + 11)*x2**2 + 2*((w1 + w3)*x1 + 6)*x2 + 1)*x3**2 + ((w1 + w3)*x1*x2**3 > + 2*((w1 + w3)*x1 + 3)*x2**2 + ((w1 + w3)*x1 + 7)*x2 + 1)*x3)*x4 + 48*x2 + > 24)*exp(-w2*x1*x2*x3*x4)/((x2**3*x3**6*exp(w5*x1*x2) + > 3*x2**3*x3**5*exp(w5*x1*x2) + 3*x2**3*x3**4*exp(w5*x1*x2) + > x2**3*x3**3*exp(w5*x1*x2))*x4**3*exp(w6*x1*x2*x3) + 3*((x2**3 + > x2**2)*x3**5*exp(w5*x1*x2) + 3*(x2**3 + x2**2)*x3**4*exp(w5*x1*x2) + 3*(x2**3 > + x2**2)*x3**3*exp(w5*x1*x2) + (x2**3 + > x2**2)*x3**2*exp(w5*x1*x2))*x4**2*exp(w6*x1*x2*x3) + 3*((x2**3 + 2*x2**2 + > x2)*x3**4*exp(w5*x1*x2) + 3*(x2**3 + 2*x2**2 + x2)*x3**3*exp(w5*x1*x2) + > 3*(x2**3 + 2*x2**2 + x2)*x3**2*exp(w5*x1*x2) + (x2**3 + 2*x2**2 + > x2)*x3*exp(w5*x1*x2))*x4*exp(w6*x1*x2*x3) + ((x2**3 + 3*x2**2 + 3*x2 + > 1)*x3**3*exp(w5*x1*x2) + 3*(x2**3 + 3*x2**2 + 3*x2 + 1)*x3**2*exp(w5*x1*x2) + > 3*(x2**3 + 3*x2**2 + 3*x2 + 1)*x3*exp(w5*x1*x2) + (x2**3 + 3*x2**2 + 3*x2 + > 1)*exp(w5*x1*x2))*exp(w6*x1*x2*x3)) from time import time as stime t0=stime() > foo=g.series(x4, 0, 7) t1=stime() print(t1-t0) > > “never” returns (i. e. doesn’t return after 40 minutes). > > FWIW, this series can be computed without problems and in short times with > Giac, Mathematica and Sage (using Sage’s series in the latter case). Maxima > standalone can compute it via taylor, but fails when called from Sage. > > Relevant posts/threads in sage-support and ask.sagemath.org. > > -- > 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/06760f72-6c19-4dd3-8b1c-edcf70a9bbdcn%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/CAHVvXxSYaxRoQMFpiD3Ojb5WR2Z%2B%2BfaDc2O%2BxbXA8sqb8NE4_w%40mail.gmail.com.
