[sage-support] Re: "Is 1 zero or nonzero?"

2018-10-24 Thread Simon King
Hi Chris, On 2018-10-23, Chris Judge wrote: > > Appears to be a bug that comes when integrating expression. > Maxima asks "Is 1 zero or nonzero?" and then suggests using assume(1>0). > Then it fails to accept this assumption... You just made my day... Coincidally, this week I told my students

Re: [sage-support] Re: "Is 1 zero or nonzero?"

2018-10-24 Thread Chris Judge
Hi Simon, The integral is sort of complicated. First integrate f(r) = r^5*(1-r^2)/((1-2*a*r+r^2)*(1-2*b*r+r^2)) over [0,1]. Sage asked for some assumptions and so I gave it these: assume( -1 < a < 1) assume( -1 < b < 1) assume(a^2-1 <0) assume(b^2-1 <0) With these assumptions, this first integr

Re: [sage-support] Re: "Is 1 zero or nonzero?"

2018-10-24 Thread Vincent Delecroix
I can not reproduce (or I misunderstood your instructions). Please provide a *complete* list of commands that lead to the problem. Here is what I got sage: a = SR.var('a') sage: b = SR.var('b') sage: f(r) = r^5*(1-r^2)/((1-2*a*r+r^2)*(1-2*b*r+r^2)) sage: assume( -1 < a < 1) sage: