How to get data from 2D array and put into 1D array

Question

I have a 2D array and I want to create a 1D by MATLAB, satisfying the requirement that each element of the 1D output was created by the value of a given index into the 2D array.

Answer 1

You are looking for sub2ind:

A=[2 4 6; 1 9 7; 3 4 5]
X=[1;2;3]; Y=[1;2;3];
B = A(sub2ind(size(A),X,Y))

B =

     2
     9
     5