Subject: asksign, was: proposal to modify op and args
From: Robert Dodier
Date: Tue, 9 May 2006 10:09:06 -0600
On 09 May 2006 15:51:06 +0200, Albert Reiner <areiner at tph.tuwien.ac.at> wrote:
> I also dislike that assumption, but the real problem are the
> questions, not the errors that can be caught easily. AFAIK there is
> no way to tell Maxima to simply give up instead of asking questions.
> Or is there?
There is no way to disable all asksign questions.
There is assume_pos and assume_pos_pred which cause asksign to
assume the expression is positive under some circumstances.
? assume_pos_pred shows some examples.
However there is no way to work around asksign, and there is yet a third
kind of asking mechanism which is used only in the integration code
to track half-integer values, if I remember correctly.
I made an attempt to revise the ask-stuff so that a conditional
expression if <positive> then <value-1> elseif <negative> then <value-2>
else <value-3> could be returned. See:
http://maxima.sourceforge.net/wiki/index.php/Noninteractive%20mode
It's no more than a proof of concept -- it is susceptible to stack
overflows, probably from failing to catch some conditions.
If you have any comment on this topic, I would be interested to hear it.
Robert