![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/255811/image.png)
Solving a non linear least square of a sum function with two unknowns
1 Ansicht (letzte 30 Tage)
Ältere Kommentare anzeigen
Hello,
i have a Chi-Square merit function with two unknown k1 and k2. Unfortunately, I don't know exactly which syntax to use to minimize this function in order to determine k1 and k2.
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/255673/image.png)
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/255674/image.png)
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/255675/image.png)
Unfortunately, I am also relatively new with Matlab. I would be very happy about a step by step explanation. I have already found out that lsqnonlin can be used as a solver.
I appreciate your help. Thank you.
2 Kommentare
Star Strider
am 18 Dez. 2019
Note that lsqnonlin fits a function to data.
Do you have a matching vector for
?
![](https://www.mathworks.com/matlabcentral/answers/uploaded_files/255811/image.png)
Akzeptierte Antwort
Matt J
am 18 Dez. 2019
Bearbeitet: Matt J
am 19 Dez. 2019
It would look like this,
kInitial = __________; %initial guess of k
kOptimal = lsqnonlin(@(k) residual(k,am,bm,cm,g,ch,bh,ah) , kInitial); %do the optimization
function r=residual(k,am,bm,cm,g,ch,bh,ah)
k1=k(1); %extract k(i) into separate variables, for convenience
k2=k(2);
numerator=cm+bm*k2+am*k1; %calculate numerator expression for all m
denominator=ch+bh*k2+ah*k1; %calculate demonator expression for all m
r=numerator./denominator - g; %calculate the vector of residuals, for all m
end
3 Kommentare
Weitere Antworten (0)
Siehe auch
Kategorien
Mehr zu Loops and Conditional Statements finden Sie in Help Center und File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!