RONALD F MODESITT <rmodesi at msn.com> writes:
> Obviously x0 is a scalar being compared to a list (lb), but I am not
> certain this is an issue.
Maxima cannot compare a scalar to a list using ">" or "<".
What do you think Maxima should do when asked, for example:
if (50 > [40,60]) ...
If you can answer that question, then I can probably suggest how to fix
your code.
> I've tried declaring ub, and lb as scalars without success.
Do you mean with `declare'? Such properties are only consulted when
`ub' or 'lb' are actually seen as _unknowns_ in an expression that is
being manipulated by Maxima.
In this case, specific list values have been assigned to `ub' and 'lb',
such that "(x0 > lb)" evaluates to something like (50 > [40,60]), and
that's what the ">" operator now sees. What you have declared about
`ub' or `lb' are now irrelevant, because those variables are no longer
present.
Best,
Mark