SIZE	Matrix dimensions.
 	D = SIZE(X), for M-by-N matrix X, returns the two-element
 	row vector D = [M, N] containing the number of rows and columns
 	in the matrix.
 
 	[M,N] = SIZE(X) returns the number of rows and columns
 	in separate output variables.
 
  	M = SIZE(X,1) returns just the number of rows.
 	N = SIZE(X,2) returns just the number of columns.