
Re: Difference of cost functions in optimization?
Posted:
Feb 21, 2013 1:38 PM


On 2/21/2013 6:16 AM, Pascal Schulthess wrote: > Hi everyone, > > I'm working quite a long time with lsqnonlin and comparable functions > but now I'm wondering if there's a difference between the following > two expressions of the cost function: > > First: > f = [0,1]; > function error = objFcn(p, x, y) > fit = zeros(size(ydata)); > for i = 1:size(ydata, 1) > fit(i,:)= p(1)*x + f(i)*p(2); > end > error = fity; > end > > And, secondly: > function error = objFcn(p, x, y) > fit = zeros(size(ydata)); > fit(1,:)= p(1)*x; > fit(2,:)= p(1)*x + p(2); > error = fity; > end > > I would really appreciate any help and possible explanations. > > Thanks a lot, > > Pascal
Well, I'm not sure what is the error or warning you are seeing, or what is the problem you are experiencing.
If I have to guess, it seems to me that the "fit" matrix has a different size in the second formulation than in the first. But I really don't know, because you haven't told us the size of your matrices.
Alan Weiss MATLAB mathematical toolbox documentation

