function L1 = CP_Laplacian( M )%UNTITLED Summary of this function goes here%   Detailed explanation goes here% number of vertices (size of matrix)nverts = size(M.vertices,1);% assume manifold and faces oriented uniformlyedges = [M.faces(:,[1,2]); M.faces(:,[2,3]); M.faces(:,[3,1])];% extract vertices from matrixv1Idxs = edges(:,1);v2Idxs = edges(:,2);v1s = M.vertices(v1Idxs,:);v2s = M.vertices(v2Idxs,:);% compute edge lengths and weightseps = 1e-8;edgel = sqrt( sum( (v1s-v2s).^2, 2 ) );edgew = 1 ./ (eps + edgel );% construct sparse matrixnnzeros = size(edges,1) / 2;L1 = sparse( v1Idxs, v2Idxs, edgew, nverts, nverts );% compute diagonal by summing column-major (faster)D = -full( sum( L1,1 ) )‘;% insert D in 0-diagonal of L1L1 = spdiags(D,0,L1);end