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椋木迪

新虫 (小有名气)

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[求助] fmincon函数求解非线性约束优化问题出错已有1人参与

我用fmincon函数求解一个非线性约束优化问题总是算不出结果，不知道哪里出问题了，求大佬帮忙看看，一下是代码：
x0=[3.6;0.8;19;7.8;7.6;3.5;5.2];
A=[];b=[];
Aeq=[];beq=[];
lb=[2.6;0.7;17;7.3;7.3;2.9;5.0];ub=[3.6;0.8;28;8.3;8.3;3.9;5.5];
[x,fval,exitflag,output,lambda,grad,hessian]=fmincon(@myfun,x0,A,b,Aeq,beq,lb,ub,@mycon);

function [c,ceq] = mycon(x)
c(1)=27/(x(1)*x(2)^2*x(3))-1;
c(2)=397.5/(x(1)*x(2)^2*x(3)^2)-1;
c(3)=1.93*x(4)^3/(x(2)*x(3)*x(6)^4)-1;
c(4)=1.93*x(5)^3/(x(2)*x(3)*x(7)^4)-1;
c(5)= 10*x(6)^(-3)*sqrt((745*x(2)^(-1)*x(3)^(-1)*x(4))^2+1.69*10^7)-1100;
c(6)=10*x(7)^(-3)*sqrt((745*x(2)^(-1)*x(3)^(-1)*x(5))^2+1.575*10^8)-850;
c(7)=(1.5*x(6)+1.9)/x(4)-1;
c(8)=(1.1*x(7)+1.9)/x(5)-1;
c(9)=x(2)*x(3)-40;
c(10)=5-x(1)/x(2);
c(11)=x(1)/x(2)-12;
ceq = [];

function y = myfun(x)
y = 0.7854*x(1)*x(2)^2*(3.333*x(3)^2+14.9334*x(3)-43.0934)-1.5079*x(1)*(x(6)^2+x(7)^2)+7.477*(x(6)^3+x(7)^3)+0.7854*(x(4)*x(6)^2+x(5)*x(7)^2);

以下是MATLAB里的提示：
Local minimum found that satisfies the constraints.

Optimization completed because the objective function is non-decreasing in
feasible directions, to within the default value of the optimality tolerance,
and constraints are satisfied to within the default value of the constraint tolerance.

<stopping criteria details>

Optimization completed: The relative first-order optimality measure, 7.082717e-09,
is less than options.OptimalityTolerance = 1.000000e-06, and the relative maximum constraint
violation, 0.000000e+00, is less than options.ConstraintTolerance = 1.000000e-06.

Optimization Metric Options
relative first-order optimality = 7.08e-09 OptimalityTolerance = 1e-06 (default)
relative max(constraint violation) = 0.00e+00 ConstraintTolerance = 1e-06 (default)
由于是第一次用MATLAB来求解优化问题，所很多地方不懂，请多多指教，谢谢各位大神了。

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