# How to find position of value in matrix and write as another matrix

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Akmyrat on 13 Aug 2014
Edited: Andrei Bobrov on 13 Aug 2014
Lets say i have this matrix
A = [1 0;
0 0;
1 1;
0 1;
0 0]
Now i want to write the positions of line of value "1" in another matrix B. In A it should start from column1. answer should be like this
B=[1 3 3 4]
which is in column1 value"1" is at 1 and 3, and in column 2 value"1" is at line 3 and 4.

the cyclist on 13 Aug 2014
Edited: the cyclist on 13 Aug 2014
[ii jj] = find(A);
B = ii';
Since you don't need the jj index, you can just do
[ii ~] = find(A);
B = ii';
Akmyrat on 13 Aug 2014
thanks a lot cyclist...Same A matrix with one more column A=[1 0 0;0 0 1;1 1 0;0 1 0;0 0 0]. i want result to be like that B=[1 3 2 3 4], which is from top to down 1 and 3 position in !st column, 2 position in 3rd column, 3 and 4 position in 2nd column. can u help please.

Andrei Bobrov on 13 Aug 2014
Edited: Andrei Bobrov on 13 Aug 2014
on Akmyrat's comment
[B,~] = find(A(:,[1 3 2]));
B = B';
Akmyrat on 13 Aug 2014
thanks a lot Andrei...:)