Searching a Matrix for Specific Values

Question

Joe 2012-11-21

I need to look for occurrences of values in a matrix, namely instances in a matrix where the rows contain the following:

1. The numbers 1 2 3 4 5, in any order 2. the number '2' twice in the same row 3. The row is comprised of entirely the same number.

Thank you

Thomas 2012-11-21

please show us what you have done so far, and where you are getting stuck.

Joe 2012-11-21

I was actually able to do the second and third part, but I'm struggling with the first part. I tried using:

ismember([1 2 3 4 5], A, 'rows')

where A the matrix I am searching, however the issue is that I can only search for that specific sequence, not all occurrences of those numbers.

Answer 1

John Petersen 2012-11-21

For matrix A

thisrow = A(row,:);
result1 = (any(thisrow,1) && any(thisrow,2) && any(thisrow,3) && any(thisrow,4) && any(thisrow,5));

This will do the first case you posed. result1 will be 1 if the row contains 1,2,3,4,&5, and will be 0 if it doesn't. This should get you started.