??? Input argument "x" is undefined.
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I want to solve a set of nonlinear equations to get a set of six parameters x(1):x(6).These are my code:
function F = ParameterEstimation(x)
T = [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12];
for T = [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12];
miu(T) = [1;2;3;4;5;6;7;8;9;10;11;12]; %%not the actual values
sigma(T)=[1;2;3;4;5;6;7;8;9;10;11;12];
delta(T)=[1;2;3;4;5;6;7;8;9;10;11;12];;
dryprob(T)=[1;2;3;4;5;6;7;8;9;10;11;12];
end
x0 = [0; 0; 0; 0; 0; 0];
for T=1:12
F = [miu(T)-(x(1)*x(6)*(1+(x(2)/x(3)))*(x(5)/(x(4)-1))*T);
k1-(2*x(1)*(1+(x(2)/x(3)))*x(6)^2+(x(1)*(1+(x(2)/x(3))*(x(6)^2)*x(3)/((x(3)^2)-1)))*(x(5)^x(4)/(x(4)-1)));
k2-(((x(1)*(1+(x(2)/x(3)))* x(2))/((x(3)^2)-1))*(x(5)^x(4)/(x(4)-1)));
sigma(T) -((((2*x(5))^(2-x(4)))/(x(4)-2)*(k1-(k2/x(3))))-(((2*x(5))^(2-x(4)))/((x(4)-2)*(x(4)-3))*(k1-(k2/x(3)^2)))+(2/((x(4)-2)*(x(4)-3)))*(k1*((T+x(5))^(3-x(4)))-(k2/x(3))*((x(3)*T+x(5))^(3-x(4)))));
delta(T) - ((k1/ (x(4)-2)*(x(4)-3))*(x(5)^(3-x(4))+(2*T+x(5)^(3-x(4)))-(2*(T+x(5))^(3-x(4))))+(k2/(x(3)^2*(x(4)-2)*(x(4)-3)))*(2*((x(3)*T+x(5))^(3-x(3))))-x(5)^(3-x(4))-((2*x(3)*T+x(5))^(3-x(4))));
f1 - ((x(1)*x(5)/(x(3)*(x(4)-1)))*(1+(x(3)*(x(2)+(x(3)/2)))-(1/4)*x(3)*(x(2)+x(3))*(x(2)+2*x(3))+(x(3)*(x(2)+x(3))*(4*x(2)^2+27*x(2)*x(3)+36*x(3)^2))/72));
f2 - (x(1)*x(5)/((x(2)+x(3))*(x(4)-1))*(1-x(2)-x(3)+(3/2)*x(3)*x(2)+x(3)^2+(x(2)^2/2)));
f3 - ((x(1)*x(5)/((x(2)+x(3))*(x(4)-1)))*(x(5)/(x(5)+T*(x(2)+x(3))))^(x(4)-1)*(1-x(4)-x(3)+(3/2)*x(3)*x(2)+x(3)^2+(x(2)^2/2)));
dryprob(T)- (exp(-x(1)*T-f1+f2+f3))];
end
options=optimset('Display','iter'); % Option to display output
[x,fval] = fsolve(ParameterEstimation,x0,options); % Call optimizer
p/s : i am very sorry since the equations are too long. but that's the real equations i hv to solve. Then, i got the error ??? Input argument "x" is undefined. and i dont know what it is and how to fix it :( please help me......
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采纳的回答
Image Analyst
2012-2-22
How did you call it? Did you assign a value to x and pass it in, something like this:
x_in = rand(7,1);
Fout = ParameterEstimation(x_in);
2 个评论
Image Analyst
2012-2-22
I don't understand this. You said you did assign initial values, so why are you asking if you still need to assign initial values? Yes, you have to assign initial values for x, even if they're all zero, and then call the function while passing x into the function like I showed.
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