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Writing a function in MATLAB
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I want to simply write this mathemtical equation in MATLAB, but I am getting some error. Please help.
13 Comments
Sam Chak
on 1 Oct 2023
The x-data in the 'Double_q.xlsx' spreadsheet is not sorted in ascending order; it appears to resemble an exponential decay when sorted in Excel.
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Accepted Answer
dpb
on 1 Oct 2023
% 1. Associate coefficients with parameter array to estimate
A --> b(1)
q1--> b(2)
q2--> b(3)
beta1>b(4)
beta2>b(5)
lambd>b(6)
% 2. Write anonymous function in b(), x
fun=@(b,x) b(1)*(b(2)*b(4)*x).^(1/(1-b(2))) + (1-b(1))*(1-(b(6)/b(5))+(b(6)/b(5))*exp((b(3)-1)*b(5)*x)).^(1/(1-b(3)));
% 3. Pick initial guess for b0 as estimates
b0=[....]; % look at the data and make some reasonable guesses for b(1) thru b(6)
% 4. Solve for b vector...
b=lsqnonlin(fun,b0);
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