MATLAB: Find given element in column 1 with “find” function.

Question

Hello all, I am trying to use "find" function and I want to find the given number in 1st column only. For example if I have a matrix A= [ 1 1 3;1 2 3;1 2 1]; and I want to find 1's in column 1 by using P=find(A==1). My ans is P= [1;2;3;4;9] which are the indexes of 1. I want only 1st column output which should be [1;2;3]. Please help if you have any idea. Thank you.

Answer 1

A = [ 1 1 3;1 2 3;1 2 1];
P = find(A(:,1)==1);