MATLAB: Binary matrix to array of poitns

Question

Hi, I have a binary image (only 0 and 1) and I want to convert it to x-y arrays.

For example:

Matrix

0 1 0 1

0 0 0 1

1 0 0 0

0 0 0 0

Obtain:

x = [1 1 2 3];

y = [2 4 4 1];

I can do it with two loops, but I'm finding something more fast. Thanks

Answer 1

>> [y,x] = find(M.')
y =
   2
   4
   4
   1
x =
   1
   1
   2
   3