Hi Doug,
On Mon, 2007-10-22 at 19:49 -0500, Doug Stewart wrote:
> I have
>
>
> exp1:a1*s*h1=(h2-h1)/r1 +u;
> exp2:a2*s*h2 = -(h2 -h1)/r1 - h2/r2;
> a1=1;
> a2=1;
> r1=.5;
> r2=1/3;
> solve([exp2,exp1],[h1,h2]);
>
> and this works but now I want to use the numerical values for a1 a2 r1 r2.
>
> How do I get a final answer.
It really depends on what you mean by "use the numerical values" and
"get a final answer". Lines like a1=1; do not cause a1 to take-on the
value on the right side of the equation. In fact, a1=1 is just an
equation, if you run the input a1; after doing a1=1; you will get the
output a1, that is, Maxima still sees a1 as a variable. If you want the
solution for h1 and h2 with the values you give substituted in you could
do the following.
exp1:a1*s*h1=(h2-h1)/r1 +u;
exp2:a2*s*h2 = -(h2 -h1)/r1 - h2/r2;
solve([exp2,exp1],[h1,h2]),a1=1,a2=1,r1=0.5,r2=1/3;
Is this what you are looking for? The equations after the solve command
work as conditions to be applied to the result.
HTH, Bob
--
Dr. Robert J. Jerrard, Professor of Mathematics,
Concordia University College of Alberta,
7128 Ada Blvd., Edmonton, Alberta, T5B 4E4, Canada.
Phone: (780) 479-9291, Fax: (780) 474-1933.