% this function takes two matrices V (eigenvectors in columns) and D (diagonal 
% matrix of eigenvalues, and sorts the columns of V by descend eigenvalue in D 
function [V2,D2]=sorteig(V,D)

    % make sorted diagonal matrix
    [d,index]=sort(diag(D),'descend'); D2=diag(d);

    % use index to sort V
    V2=V(:,index);

% done