commGSP/commGSP_eig.m
234a68af8299master

commGSP_eig.m
View Options

			function [U, D] = commGSP_eig(A, order)
			% Eigendecomposes provided matrix with eigenvalues of given ordering
			% INPUT:
			% A - (symmetric) matrix to decompose
			% order - string equal to 'ascend' or 'descend' (for eigenvalue order)
			% OUTPUT
			% U - eigenvector matrix (column-wise)
			% D - eigevalue matrix (diagonal)

			A=(A+A')./2;
			[U,D] = eigs(A, size(A,1));
			eigv=diag(D);
			eigv(find(abs(eigv)<1e-9))=0;
			[eigv, ind] = sort(eigv, order);
			D = sparse(diag(eigv));
			U = sparse(U(:,ind));

			end