Hello, I am relatively new to matlab and it's function handle approach.

I am trying to calculate the largest eigenvalue of a very large sparse matrix for which I only have a function. My code looks something like this (the part where the error occurs):

`function s=my_function(A)hand=@(x) Multiply_by_Ar(A,x);s=eigs(hand,1);`

The function Multiply_by_Ar returns, for a given A and x, the vector Ar*x, where the matrix Ar is related to A, but not equal to it. I then make a function handle which is basically multiplying by Ar and use the eigs function. It returns the problem

`??? Subscripted assignment dimension mismatch.Error in ==> eigs>fullEig at 1188 AA(:,i) = A(AA(:,i),varargin{afunNargs});Error in ==> eigs at 104 fullEig(nargout);Error in ==> s_radij_SOR at 6 s=eigs(rocka,1);`

Which I do not understand. Please help.

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