How to optimize this equation using GA tool?

8 次查看（过去 30 天）
Raja
Raja 2013-7-25
Hi all, I have polynomial equation: y =89.81+1.96*x(1)-3.02*x(2)-1.46*x(1)^2-1*x(2)^2-4.45*x(3)^2-1.57*x(1)*x(3)-2.74*x(2)*x(3) and I am looking for optimization of the above equation with Lower bounds [-1.68 -1.68 -1.68] and Upper bounds [1.68 1.68 1.68]. When I feed this equation in GA tool and run....I get an output of
"Objective function value: 56.37940293199839 Optimization terminated: average change in the fitness value less than options.TolFun."
But for the same equation, by polynomial regression I get an output of 94.73! can anybody help?

请先登录，再回答此问题。

采纳的回答

Alan Weiss
Alan Weiss 2013-7-25
I don't understand what you think the problem is. The objective function that ga found is better than the one you get by "polynomial regression." So is your problem that ga got a better answer? Or that you think the answer is wrong?
I just ran your problem, and here is what I got:
fun = @(x)89.81+1.96*x(1)-3.02*x(2)-1.46*x(1)^2-1*x(2)^2-4.45*x(3)^2-1.57*x(1)*x(3)-2.74*x(2)*x(3);
lb = -1.68*ones(3,1);
ub = -lb;
[x,fval] = ga(fun, 3,[],[],[],[],lb,ub)
Optimization terminated: average change in the fitness value less than options.TolFun.
x =
1.6789 1.6800 1.6800
fval =
56.3686
Checking with fmincon shows that this is a good answer.
Alan Weiss
MATLAB mathematical toolbox documentation

更多回答（0 个）

类别

在 Help Center 和 File Exchange 中查找有关 Solver Outputs and Iterative Display 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by