integrating trig functions with large constants, exponent out of range
Subject: integrating trig functions with large constants, exponent out of range
From: Daniel Lakeland
Date: Fri, 5 Jan 2007 18:31:51 -0800
On Fri, Jan 05, 2007 at 03:51:45PM -0800, Daniel Lakeland wrote:
> On Sat, Jan 06, 2007 at 01:10:07AM +0200, Neilen Marais wrote:
> > Hi
> >
> > I get the following problem:
> >
>
> > I tried reducing the error:
> >
> > (%i9) integrate(%i*sin(34037595938027*x3)*x3, x3);
> >
> > but had to interrupt it since it seemed to take forever. I found that
> > the integration time is dependent on the size of the constant in the
> > expression. integrate(%i*sin((3*x3))*x3, x3) happens fast,
> > integrate(%i*sin((30000*x3))*x3, x3) takes several seconds etc.
>
> This executes in no time flat for me on windows stock maxima 5.10.0 in
> GCL.
>
> ****** It also gives a wrong answer!!! ******
>
The debian package 5.10.0-6 on amd64 has the same hanging behavior
that you see rather than the fast wrong answer.
--
Daniel Lakeland
dlakelan at street-artists.org
http://www.street-artists.org/~dlakelan