All m combinations of the first n integers taken p at a time
are computed and return as an p by m matrix. The columns
of the matrix are ordered so that adjacent columns differ
by only one element. This is just a reordered version of
combn in base R, but the ordering is useful for some
applications.
Usage
combos(n,p)
Value
a matrix of dimension p by choose(n,p)
Arguments
n
The n in n choose p
p
The p in n choose p
References
Limin Xiang and Kazuo Ushijima (2001)
"On O(1) Time Algorithms for Combinatorial Generation,"
Computer Journal, 44(4), 292-302.