# Find row(s) of 3x3 matrix where the 1st and 2nd column equals a value

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Sebastian Daneli on 27 Apr 2020
Commented: Sebastian Daneli on 27 Apr 2020
Hi
I have a 3x3 matrix, and i would like to find the rows where the 1st and 2nd columns equals a value.
M=[1 2 3
1 1 3
2 1 3]
Lets say I would like to find the row where both the 1st and 2nd column equals 1. In this case i would like to find row 2, and be able to extract the values of that row, i.e. 1 1 3.

Sriram Tadavarty on 27 Apr 2020
Edited: Sriram Tadavarty on 27 Apr 2020
Hi,
Try this:
out = M(M(:,1)==1 & M(:,2)==1,:); % For the example provided with value 1
% For any generic value
out = M(M(:,1)== M(:,2),:);
Hope this helps.
Regards,
Sriram

#### 1 Comment

Sebastian Daneli on 27 Apr 2020
Thanks, this is what I call customer service

Ameer Hamza on 27 Apr 2020
Edited: Ameer Hamza on 27 Apr 2020
M = [1 2 3
1 1 3
2 1 3];
idx = M(:,1)==M(:,2);
M_new = M(idx,:);
Result:
>> M_new
M_new =
1 1 3

#### 1 Comment

Sebastian Daneli on 27 Apr 2020
Thanks