Re: Bug in Calc? (was Re: Non-commutative symbolic multiplication in Calc)

[Jay Belanger]

Neon Absentius <absent@sdf.lonestar.org> writes:
...
> Alas, there seems to be a bug: After I give 'm v' if I ask calc to
> simplify the expression 'a b - b a' it leaves it as is which is as 
> expected. However when I ask it to expand '(a+b)^2' it returns 
> 'a^2 + 2 b a + b^2' which is of course wrong if a and b don't commute. 
> This happens both with emacs-multi-tty (22.0.50) and whith emacs
> 21.4.1 on a Debian testing/unstable. The bug manifsts itself also
> for the expansion of '(a+b)^3' however calc expands '(x+y)(x-y)'
> into 'x^2 + y x  -  x y + y^2'. Strange!

This should be fixed in CVS.

Jay