Suppose I have an array of size 2*2, eg. A=[1 2 3 4], which is a representation of the matrix A=[1 3 ; 2 4] (column major format) . Now I wish to convert the array into A=[1 2 0 3 4 0 0 0 0], which is a representation of the matrix [1 3 0; 2 4 0;0 0 0]. How can I achieve this conversion?