MATLAB: Counting average on huge matrix with conditional

averagematrix

The following code runs forever on 10^5 square matrix A. It runs a few seconds on 10^3 square matrix. Is there any way to speed it up?
   function [meanNV]=calcMeanNV_k(A,V,d)
%A: input matrix (n x n)
%V: eigenvectors of k-th largest eigenvalues (n x 1)
%d: degrees of each node (n x 1)
%meanNV: mean of neighbors vectors (n x 1)
m=size(A,2);
meanNV=zeros(113336);
 for i=1:m
     sumNode = 0;
     for j=1:m
        if A(i,j)==1
            sumNode=sumNode+V(j);
        end
     end
    [meanNV(i)]=sumNode/d(i); 
 end

Best Answer

It seems this is likely what you are looking for then:
function [meanNV]=calcMeanNV_k(A,V,d)
%A: input matrix (n x n)
%V: eigenvectors of k-th largest eigenvalues (n x 1)
%d: degrees of each node (n x 1)
%meanNV: mean of neighbors vectors (n x 1)
m=size(A,2);
meanNV=zeros(113336);
idx = A == 1;
for k = 1:m
   meanNV = sum(V(idx(k,:)));
end
meanNV = meanNV./d
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