How to fix error of this type: "Failure in initial user-supplied objective function evaluation. FSOLVE cannot continue"

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I am trying to solve a system of nonlinear equations with fsolve command. The function script is:
function F = eqn1(z)
z(6) = 0.01:0.01:0.01;
F(1) = z(1) + z(2) + z(3) -1;
F(2) = z(4) + z(5) + z(6) -1;
F(3) = z(1).*(10.^((1.167.*(z(2)).^2 +0.8085.*z(2).*z(3))./((z(1)+1.168.*z(2)+z(3)).^2))) - z(4).*(10.^((1.167.*(z(5)).^2 +0.8085.*z(5).*z(6))./((z(4)+1.168.*z(5)+z(6)).^2)));
F(4) = z(2).*(10.^((1.733.*(z(1)).^2 +0.383.*z(1).*z(3)+0.046.*(z(3)).^2)./((z(2)+0.856.*z(1)+z(3)).^2)) - z(5).*(10.^((1.733.*(z(4)).^2 +0.383.*z(4).*z(6)+0.046.*(z(6)).^2))./((z(5)+0.856.*z(4)+z(6)).^2)));
F(5) = z(3).*(10.^((2.019.*(z(2)).^2 -0.4252.*z(2).z(1))./((1.168.*z(2)+3.5215.*z(1)+z(3)).^2))) - z(6).*(10.^((2.019.*(z(5)).^2 -0.4252.*z(5).*z(4))./((1.168.*z(5)+3.5215.*z(4)+z(6)).^2)));
end
And the call to fsolve is:
fun = @eqn1;
z0 = [1 0 0 0 1];
z = fsolve(fun,z0)
but its showing
Error in eqn2_solver (line 3)
z = fsolve(fun,z0)
Caused by:
Failure in initial user-supplied objective function evaluation. FSOLVE cannot continue.
How can I fix this?? Thanks!!

Answers (1)

Alex Sha
Alex Sha on 24 May 2019
Hi,“z(2).z(1)” should be "z(2).*z(1)"

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