On Dec 12, 10:11 pm, Dan Drake <[email protected]> wrote: > I'm doing some integrals: > > sage: a, b, t = var('a b t') > sage: f(a,b,t) = sin(t)^2/(a + b*cos(t))^2 > sage: integrate(f(3/2,1,t), (t,0,2*pi)) > -2/5*(sqrt(5) - 3)*pi*sqrt(5) > > Okay, that's fine. But > > sage: integrate(f(1.5,1,t), (t,0,2*pi)) > > blows up with: > > RuntimeError: ECL says: Error executing code in Maxima: CRECIP: > attempted inverse of zero (mod 3) > > This is with 4.7.2 on 64-bit Ubuntu. I get the same error on sage.math. > > How on earth is it trying to invert something mod 3?
Hmm, not obvious to me. I can get it to happen on Mac, but I can't get it to happen in the Maxima console. (%i1) display2d:false; (%o1) false (%i2) h:sin(t)^2/(cos(t)+1.5)^2; (%o2) sin(t)^2/(cos(t)+1.5)^2 (%i6) integrate(h,t,0,2*%pi); rat: replaced 1.5 by 3/2 = 1.5 rat: replaced 1.5 by 3/2 = 1.5 rat: replaced 1.5 by 3/2 = 1.5 rat: replaced 1.5 by 3/2 = 1.5 rat: replaced 1.5 by 3/2 = 1.5 (%o6) -2*%pi Can you open a ticket and cc: me? - kcrisman -- To post to this group, send an email to [email protected] To unsubscribe from this group, send an email to [email protected] For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
