How to count repetition of a row in a matrix?

I have a matrix: M = [1,2; 2,3; 1,5; 2,3; 1,4; 1,6; 2;3, 8,9]; And I want to check number of occurance of a given row, for example [2,3]. How to do that without for cycle?

Answer 1

[Stephen23]

>> M = [1,2; 2,3; 1,5; 2,3; 1,4; 1,6; 2,3; 8,9];
>> R = [2,3];

Method one: eq: and all:

>> nnz(all(M==R,2))
ans =  3

For MATLAB versions before R2016b use bsxfun and eq:

>> nnz(all(bsxfun(@eq,M,R),2))
ans =  3

Method two: ismember:

>> nnz(ismember(M,R,'rows'))
ans =  3

[Mr M.]

sum(ismember(M,R,'rows')) is the same?