how to load(sign-shift.lisp) in wxmaxima 0.8.0

Am Sonntag, den 11.10.2009, 12:43 +0800 schrieb ? ??:
> how to load(sign-shift.lisp) in wxmaxima 0.8.0
> 
> I read form Maxima Digest, Vol 39, Issue 33 and  try to
> load(sign-shift.lisp)
> (%i4) load(sign-shift.lisp)
> Could not find `sign-shift.lisp' using paths in
> file_search_maxima,file_search_lisp.
>  -- an error.  To debug this try debugmode(true);

Thank you very much for your interest.

The code is under development. You cannot download it. You can try to
cut it out of the postings. But I think you might have some problems to
get it to work. 

First I have thought that I have found a simple way to improve the
functionality of assume in general. The code as it is, works with the
testsuite and the share_testsuite.

But there is a big problem. The code improves cases like assume(a>1,b>1)
and gets the correct sign for sign(a+b-2). It works for much more
complicated expressions too, but not as general as I thought. We do not
have very general examples in the testsuite, because we do not assume
that this more general cases will work.

If we improve the assume database further the user might ask questions
like sign(a+sin(b)-2). If the symbol is an argument of a function we
will get problems. The code has to be further extended.

Now, I am not sure if it is worth to improve Maxima in a first step to
handle the actual problem.

Dieter Kaiser