I have a matrix A
1 4 2 3 4 3 1 2 3 2 4 1 2 1 3 4
How to make different groups of two elements from this matrix? But the chosen elements (from the matrix A) have to be adjacent in the matrix A. for example A(1,1) & A(1,2) are adjacent and so they can be chosen. and A(1,1) & A(4,3) can't be chosen to make a group. I'd like to create a function which randomly choose these elements from A. And the function generates an other matrix containing the (2 by 2) different groupements randomly created. (for other examples see comment below)
There are 24 four connected pairs. Three per row, three per column.
I would generate a random integer from 1-numel(A) I would generate a random direction from 1-4 (North East South West) If the starting point and direction bring you out of the matrix. Draw again.
If it is a valid pairing, subset out what you are looking for using any indexing method you prefer.