Failure in initial objective function evaluation. FSOLVE cannot continue.

I want to use fsolve in loop so that every time 'a' change, my X(1) value change and my other values change accordingly. Can anyone help with it And Also can you plot x1 and y1? Any help would be appreciated.

function F = Sample13(X,a)

x1=X(1);

x2=X(2);

y1=X(3);

y2=X(4);

p1sat=X(5);

p2sat=X(6);

p=X(7);

t=X(8);

f1 = p1sat-(exp(16.59158 -(3643.31/(t -33.424))));

f2 = p2sat-(exp(14.25326 -(2665.54/(t -53.424))));

f3 = p - 101.325;

f4 = x1 - a;

f5 = x1 + x2 - 1;

f6 = y1 + y2 - 1;

f7 = (y1*p)-(x1*p1sat);

f8 = (y2*p)-(x2*p2sat);

F=[f1;f2;f3;f4;f5;f6;f7;f8];

end

To Run Function M using this command:

fhandle=@Sample13;

for a=1:0.05:2

X0 = [0.5,0.5,0.5,0.5,200,200,101.325,333.9];

options = optimset('display','off');

X = fsolve(fhandle,X0,options);

disp(X)

end

Answer 1

[Mischa Kim]

Ahmed, use the following:

fhandle = @Sample13;
options = optimset('display','off','Algorithm','levenberg-marquardt');
a       = 1:0.05:2;

for ii = 1:numel(a)
    X0      = [0.5,0.5,0.5,0.5,200,200,101.325,333.9,a(ii)];   
    X       = fsolve(fhandle,X0,options);
    disp(X)
end

function F = Sample13(X)
x1=X(1);
x2=X(2);
y1=X(3);
y2=X(4);
p1sat=X(5);
p2sat=X(6);
p=X(7);
t=X(8);
a = X(9);
f1 = p1sat-(exp(16.59158 -(3643.31/(t -33.424))));
f2 = p2sat-(exp(14.25326 -(2665.54/(t -53.424))));
f3 = p - 101.325;
f4 = x1 - a;
f5 = x1 + x2 - 1;
f6 = y1 + y2 - 1;
f7 = (y1*p)-(x1*p1sat);
f8 = (y2*p)-(x2*p2sat);
F=[f1;f2;f3;f4;f5;f6;f7;f8];
end

Essentially, you treat a as another function input.

[Ahmed Saleem]

Thnx mate.