eigenvector

I use a function at Matlab: [V,D] = eig(C); I see that V and D are always sorted ascending order. Does it always like that or should I sort them after I get V and D values? V is NOT sorted in any order, except to correspond to the order of the associated eigenvalues. But perhaps you did not mean that. The eigenvalues TEND to be in descending order, but this is not assured at all. They tend to be in order because the largest tend to trickle out of the algorithm on top. Eig has no sort at the end to ensure that fact. I might point out the eigenshuffle tool, designed to take a sequence of

I'm trying to write a program that gets a matrix A of any size, and SVD decomposes it: A = U * S * V' Where A is the matrix the user enters, U is an orthogonal matrix composes of the eigenvectors of A * A' , S is a diagonal matrix of the singular values, and V is an orthogonal matrix of the eigenvectors of A' * A . Problem is: the MATLAB function eig sometimes returns the wrong eigenvectors. This is my code: function [U,S,V]=badsvd(A) W=A*A'; [U,S]=eig(W); max=0; for i=1:size(W,1) %%sort for j=i:size(W,1) if(S(j,j)>max) max=S(j,j); temp_index=j; end end max=0; temp=S(temp_index,temp_index); S