Failure in initial objective function evaluation. in fgoalattain

Hi Guys

I got some problem to run this code:

funn = @(x,y,z)[(0.42305*x+0.043383*y+0.16814*z-0.78716).^2;(-0.631363873*x-0.258982921*y+0.501872413*z-0.338137333).^2;(-22.09773556*x+4.532201111*y-35.13106889*z+30.95699333).^2];

goal = [0,0,0];

weight = [1,1,1];

x0 = [1 1 1];

[x,fval,attainfactor,exitflag]= fgoalattain(funn,x0,goal,weight,[],[],[],[],[1 1 1],[1.1 1.1 1.1])

The error said that there is a failure in initial objective function evaluation.

Could anyone help me about this error? Much appreciated!

Best regards

Xu Li

Answer 1

[Riccardo Scorretti]

Hi Li,

the error is that funn requires three arguments, whereas fgoalattain needs a function with a single argument.

To fix the problem it is enough to rewrite x = x(1), y = x(2) and z = x(3):

% funn = @(x,y,z)[(0.42305*x+0.043383*y+0.16814*z-0.78716).^2;(-0.631363873*x-0.258982921*y+0.501872413*z-0.338137333).^2;(-22.09773556*x+4.532201111*y-35.13106889*z+30.95699333).^2];

funn = @(x)[(0.42305*x(1)+0.043383*x(2)+0.16814*x(3)-0.78716).^2;(-0.631363873*x(1)-0.258982921*x(2)+0.501872413*x(3)-0.338137333).^2;(-22.09773556*x(1)+4.532201111*x(2)-35.13106889*x(3)+30.95699333).^2];
goal = [0,0,0];
weight = [1,1,1];
x0 = [1 1 1];
[x,fval,attainfactor,exitflag]= fgoalattain(funn,x0,goal,weight,[],[],[],[],[1 1 1],[1.1 1.1 1.1])

Local minimum possible. Constraints satisfied.

fgoalattain stopped because the size of the current search direction is less than
twice the value of the step size tolerance and constraints are 
satisfied to within the value of the constraint tolerance.

x = 1×3

1.0000 1.1000 1.0000

fval = 3×1

0.0220 0.5663 453.1104

attainfactor = 453.1104

exitflag = 4