MATLAB: How to quickly find the column index of the last non-zero element in all rows in a sparse matrix

last non-zero element in a rowsparse matrix

Hi, All,
I have a big sparse matrix A. I want to find out the column index of the Last non-zero element in all rows from the end. Here is my code:
reorderRow = [];
for jRow = 1 : length(A(:,1))
eee = find(A(jRow,:),1,'last');
reorderRow = [reorderRow eee];
end
For example, I have matrix A = [2 0 0;0 5 0;0 0 1;0 3 0;-1 0 -4]. My code gives the following result:
reorderRow = [1 2 3 2 3];
I am wondering if it is possible to obtain reorderRow without iterations. Thanks a lot.
Benson

Best Answer

reorderRow = arrayfun(@(X)  find(A(X,:),1,'last'), 1:size(A,1))
reorderRow =
     1     2     3     2     3
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