Hi,
I got another problem relating to this question http://ask.sagemath.org/question/8137/unable-to-make-sense-of-maxima-expression/ and many other of that kind (sorry for opening another question). If I use
sum(-1**(i+1)/(2*i-1)**3*(sin(pi*(2*i-1)/2*(r1+r2))*sin(pi*(2*i-1)/2*(r1-r2))),i,1,oo)
in the shell, I get
TypeError: unable to make sense of Maxima expression 'imagpart(f[4,3]([1/2,1/2,1/2,1],[3/2,3/2,3/2],e^-(2*I*pi*r1)))' in Sage
I'm using Sage v6.2 on a LinuxMint machine.