MATLAB: How to check and update one matrix by comparing the element of another matrix

matrixmatrix arraymatrix manipulation

I have a matrix 10*3
     1     2     3
     1     2     4
     1     2     5
     1     3     4
     1     3     5
     1     4     5
     2     3     4
     2     3     5
     2     4     5
     3     4     5
now i want to check whether second and third column pairs are existing in another 10 by 2 matrix or not
example:
     1     2
     1     3
     1     4
     1     5
     2     3
     2     4
     2     5
     3     4
     3     5
     4     5
and if any pair from 10 by 3 matrix is not able to satisfy the condition will be removed.
for example:
in first row 1 2 3 — 2 3 is available in 10*2 matrix so will keep that row as it is but if this condition is not satisfied, the entire row will be removed from 10*3 matrix
please please help me.

Best Answer

Use ismember with the 'rows' option:
A = [1 2 3; 1 2 4; 1 2 5; 1 3 4; 1 3 5; 1 4 5; 2 3 4; 2 3 5; 2 4 5; 3 4 5];
B = [1 2; 2 3; 4 5]; %reduced second matrix so some rows of A are missing
isrowpresent = ismember(A(:, [2 3]), B, 'rows');
A(~isrowpresent, :) = [] %delete rows not present
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