On 9/26/07, Ismael Garrido <ismaelgf at adinet.com.uy> wrote:
> I forgot to say that I did:
>
> (%i12) postfix("'");
> (%o12) '
> (%i13) u':= 'diff(u,t);
> (%o13) 'u:='diff(u,t,1)
>
> And that seems to be the cause of trigsimp breaking.
Well, given that single quote ' has an existing definition in Maxima
and it is widely used, it seems like redefining ' could easily cause
a lot of problems.
For the record I find that
matrix([cos(phi)*('diff(r,t,1))-sin(phi)*('diff(phi,t,1))*r],[sin(phi)*('diff(r,t,1))+cos(phi)*('diff(phi,t,1))*r])=matrix([(-cos(phi)*sin(phi)^2-cos(phi)^3)*r^3+(sin(phi)+cos(phi))*r],[(-sin(phi)^3-cos(phi)^2*sin(phi))*r^3+(sin(phi)-cos(phi))*r]);
trigsimp (%);
succeeds in both Maxima 5.10.0 and 5.13.0 (Windows).
Hope this helps,
Robert Dodier