[R] give all combinations

Carl Witthoft carl at witthoft.com
Mon Sep 1 18:19:07 CEST 2008


I seem to be missing something here:

given a set X:{a,b,c,whatever...}
the mathematical definition of 'permutation' is the set of all possible 
sequences of the elements of X.
The definition of 'combination' is all elements of 'permutation' which 
cannot be re-ordered to become a different element.

example:  X:{a,b,c}

perm(X) = ab, ab, bc, ba, ca, cb
comb(X) = ab, ac, bc


So maybe a better question for this mailing list is:  Are there 
functions available in any R package which produce perm() and comb() 
(perhaps as well as other standard combinatoric functions) ?

Carl



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