# Extracting a matrix by row and column from a large matrix

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Tanmoyee Bhattacharya on 21 May 2019
Commented: Adam Danz on 21 May 2019
I have a matrix like
1 1 1 2000
1 1 1 2000
1 1 1 2000
2 2 2 3000
2 2 2 3000
2 2 2 3000
3 3 3 5000
3 3 3 5000
3 3 3 5000
I have another matrix
2 2 2
2 2 2
2 2 2
I want a matrix from this matrix large matrix given above
2 2 2 3000
2 2 2 3000
2 2 2 3000
Can anyone help to extract the values through matlab.I am trying throuh ismember but not working.
Bob Thompson on 21 May 2019
What kind of conditions are you hoping to meet, or do you literally just want any row which contains [2 2 2 3000]?
Adam Danz on 21 May 2019
I have another matrix
2 2 2
2 2 2
2 2 2
I have to extract the 4,5,6 row and four column from the large matrix by the given matrix
2 2 2 3000
2 2 2 3000
2 2 2 3000

Adam Danz on 21 May 2019
Edited: Adam Danz on 21 May 2019
I changed your example matrix a bit to make sure it ignores partial pattern matches.
m = [1 1 1 2000
1 1 1 2000
1 1 1 2000
2 2 2 3000
2 2 2 3000
2 2 2 3000
3 3 3 5000
3 3 3 5000
3 3 3 5000
2 2 2 6000
2 2 2 6000
9 9 9 7000];
s = [2 2 2
2 2 2
2 2 2];
[~, rowIdx] = intersect(m,s);
mSubset = m(rowIdx+(0:size(s,1)-1),:);
Result
mSubset =
2 2 2 3000
2 2 2 3000
2 2 2 3000
Note that if there is more than 1 match it will only return the first subset match.