Switching off follow-up questions?



Hi,

We are working on integrating Maxima into a student homework system.  
One odd issue we ran into is that if the student enters a variable  
that is not defined, under certain circumstances, Maxima starts  
asking following questions, for example:

(%i2) overlap: integrate((6*cos(9*x)+6*sin(8*x))*(j-x),x,-%pi,%pi)/%pi;
Is  j  positive, negative, or zero?

- that's an excellent question, but doesn't work for us, since we are  
not running interactively. Is there a way to tell Maxima to just  
throw an error?

Thanks!

- Gerd.
--
Gerd Kortemeyer, Ph.D.
Michigan State University
http://www.lite.msu.edu/kortemeyer/