Simple Matrix Reduction Question. Ones and Zeros.

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I have a NxM matrix full of ones and zeros. Each row (1:N) has exactly one, one, somewhere along of the columns. I want to make a matrix Nx1 which shows which columns the ones appeared in. Example:
A = [ 0 0 0 1; 1 0 0 0; 0 1 0 0; 0 0 1 0]
B = [ 4 ; 1 ; 2 ; 3 ]
Should be very simple?

Accepted Answer

Birdman
Birdman on 1 Apr 2020
Edited: Birdman on 1 Apr 2020
[rows,cols]=find(A==1);
[C,I]=sort(rows);
B=cols(I)

More Answers (1)

Stephen23
Stephen23 on 1 Apr 2020
Simpler:
>> [B,~] = find(A.')
B =
4
1
2
3

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