The RANCOMB function generates random combinations of k elements taken from a set of elements. The random number seed is set by the RANDSEED subroutine.

The first argument, set, can be a scalar or a vector. If set is a scalar, the function returns indices in the range 1–. If set is a vector, the number of elements of the vector determines and the RANCOMB function returns elements of set.

By default, the RANCOMB function returns a single random combination with one row and columns. If the numcomb argument is specified, the function returns a matrix with numcomb rows and k columns. Each row of the returned matrix represents a single combination.

The following statements generate five random combinations of two elements from the set :

n = 4; 
k = 2;
call randseed(1234);
c = rancomb(n, k, 5); 
print c;

The function can return combinations for arbitrary numerical or character matrices. For example, the following statements generate five random pairwise combinations of four elements:

d = rancomb({A B C D}, 2, 5); 
print d;