# Fmincon solution is same as initial guess

2 views (last 30 days)
Samy Alkhayat on 14 Jul 2021
Hello,
My Fmincon function does not minimize the cost function, instead, it reports the same initial guess provided to it. Please help with recommendations to the piece of code below:
function J=cost_function(y)
for i=1:size(a,1)
AA = y0*b(i,:)';
BB = y0*c(i,:)';
CC = (y0(1).*c(i,1)/BB)*c(i,1) + (y0(2).*c(i,2)/BB)*c(i,2);
DD = y0*d(i,:)';
EE = y0*e(i,:)';
all(i,:)=[AA, BB, CC, DD, EE];
end
J=sum(abs(all(1,:) - x(1:5)') ./ x(1:5)')^2;
The script calculates the a, b, c, d, e,....... and passes them to the function along with "y0".

Sulaymon Eshkabilov on 14 Jul 2021
Edited: Sulaymon Eshkabilov on 14 Jul 2021
THere are a couple of errs oin your fcn, i.e. y0, a,b,c,d not defined. Moreover, x is not defined.
function J=cost_function(y0, a, b, c, d, e, x)
for i=1:size(a,1)
AA = y0*b(i,:)';
BB = y0*c(i,:)';
CC = (y0(1).*c(i,1)/BB)*c(i,1) + (y0(2).*c(i,2)/BB)*c(i,2); % Check: multiplied and divided by c(i,1) and c(i,2)
DD = y0*d(i,:)';
EE = y0*e(i,:)';
all(i,:)=[AA, BB, CC, DD, EE];
end
J=sum(abs(all(1,:) - x(1:5)') ./ x(1:5)')^2;
Sulaymon Eshkabilov on 15 Jul 2021
Most welcome!

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