1. ## a nonlinear problem

I am not sure that I post at the right palce, because I don't know which topic my problem should belong to. So sorry for that.

Given some variables a1, a2, a3... an, and some constraints based on these variables, like:
a1 + a2 >0,
a3 - a5 >0,
a4 - a3 + a2 <0,
....
How to get a solution for variables, that maximun the positive number of variables. That means, make as much of
steve

2. In general, if you have a non-linear problem in which you have to maximise or minimise something whilst paying due consideration to constrain equations, it's a problem of non-linear programming.

$\displaystyle \max_{c} (a_1, a_2, a_3, ..., a_n)$ where $c$ represents your constraint equations.

3. But is there any practical way to solve it?

4. Try gnumeric.

5. Originally Posted by zhu1984
I am not sure that I post at the right palce, because I don't know which topic my problem should belong to. So sorry for that.

Given some variables a1, a2, a3... an, and some constraints based on these variables, like:
a1 + a2 >0,
a3 - a5 >0,
a4 - a3 + a2 <0,
....
How to get a solution for variables, that maximun the positive number of variables. That means, make as much of