simplification based on assumptions



On 8/1/06, Richard Fateman <fateman at cs.berkeley.edu> wrote:
>
> ...it sometimes happens that Maxima's knowledge is not used in all
> the places that it might be used for reasons of efficiency...
>
> How much work do you want "for i:a step b thru c do ...  when it compares
> a+i*b to c?  I haven't looked at the code, but I would be surprised if
> assumptions were used there. :)
>

Actually, this code does seem to use asksign:

    assume(q>3 and q<4)$
    for i thru q do print(i)$
       1
       2
       3

    assume(equal(q,3))$
    for i thru q ...                    same thing

But asksign is currently so weak that some simple cases aren't handled:

    assume(equal(t,u))$
    for i:t thru u do print(i);
    t               -- OK so far
    Maxima was unable to evaluate the predicate: t + 1 > u -- error

Is anyone actively working on compar?

         -s