Am Sonntag, den 01.03.2009, 01:31 +0100 schrieb Dieter Kaiser:
> I have observed the reported bug working on the code of $laplace. If we
> correct a bug in the lisp function createname we get a lot of more
> integrals with $laplace.
>
> I have done some further improvements and added the code to call
> $specint when $laplace fails. Next I have tried the modified $laplace
> function with all integrals of the test file rtest_hypgeo.mac.
>
> With the modifications up to now almost all integrals can be solved
> calling $laplace too.
>
> But some types of integrals do not work. $laplace does not return from a
> call.
>
> One reason I have found is that the integral in the bug report does not
> work. $laplace has an recursive integration algorithm which is called
> for some types of integrals. The reported integral is generated
> internally in this recursive algorithm.
With the fix which has Dan Gildea checked in today the Laplace
transformation of sin(t)/t^2 works as expected. We get the noun form and
$laplace no longer hangs:
(%i3) laplace(sin(t)/t^2,t,s);
(%o3) 'laplace(sin(t)/t^2,t,s)
Dieter Kaiser