On 3/24/07, Stavros Macrakis <macrakis at alum.mit.edu> wrote:
> On 3/24/07, Robert Dodier <robert.dodier at gmail.com> wrote:
> > A better solution is to rework the evaluation of Boolean
> > expressions so that Maxima doesn't barf on stuff like
> > (- 1 < x and x < 1).
>
> Agreed.
OK, well, I'm glad to hear that we are in agreement on this point.
> > > A smarter charfun would know that charfun(x>0,x<0) = 0...
> > The place to put that would be in the evaluation of Boolean expressions.
>
> No!! That has nothing to do with evaluation and everything to do with
> simplification!!!
Well, my point is that deducing (x > 0 and x < 0) is always false
should happen in the processing of the Boolean expression,
not in charfun. If it is to be a simplification then I'm happy with that.
Robert