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Find rows in matrix where entries match certain constraints?

In Matlab, i have a matrix (MxN) and I want to find the rows whose entry in a specific column is equal to a specified value. For example, I have a matrix as follow:

   0    0   0   0   0   0   0   0   1   0
   1    0   0   0   0   0   1   0   0   1
   0    0   1   0   0   0   0   0   0   0
   0    0   0   1   0   0   0   0   1   0
   0    0   0   0   1   0   0   0   0   1
   0    0   0   0   0   0   0   0   0   0
   0    1   1   0   0   0   1   0   1   0
   0    0   0   0   0   0   0   0   0   1
   0    0   0   0   0   0   0   0   0   0
   0    0   0   0   0   0   0   0   0   1

I want to find the rows whose 7th element us equal to 1. In this example, the result matrix should contains rows 2 and 7.

Answer 1

if your matrix is called A, just do:

A(A(:,7)==1,:)

PS: I think that this question has already been answered a million times…