On Sun, Mar 23, 2008 at 4:44 PM, Robert Dodier <robert.dodier at gmail.com> wrote:
> > (%i1) integrate(cos(a*x)/(1+x^2),x,0,inf);
> > Is a positive, negative, or zero? zero;
> > Maxima encountered a Lisp error:
> > Error in PROGN [or a callee]: Caught fatal error [memory may be damaged]
>
> Thanks for this bug report.
>
> It appears that the bug originates from a MRAT expression which
> some function isn't prepared to handle ... The following patch fixes
> this bug. Not sure yet what other effect it might have.
>
> --- src/defint.lisp 17 Feb 2008 20:54:22 -0000 1.55
> +++ src/defint.lisp 23 Mar 2008 15:59:15 -0000
> @@ -1015,7 +1015,7 @@
> (eq ($sign (m+ (deg (setq nn* ($imagpart (caddr term))))
> -2.))
> '$neg))
> - (cond ((eq ($asksign (ratcoef nn* var)) '$pos)
> + (cond ((eq ($asksign (ratdisrep (ratcoef nn* var))) '$pos)
> (setq *updn t))
> (t (setq *updn nil)))
> term)
>
> FWIW
However, substituting a by 0, gives the following:
(%i3) integrate(cos(0*x)/(1+x^2),x,0,inf);
(%o3) %pi/2
Paul