Re: A Question about Combinatorica

*To*: mathgroup at smc.vnet.net*Subject*: [mg102655] Re: A Question about Combinatorica*From*: Helen Read <hpr at together.net>*Date*: Sun, 23 Aug 2009 05:33:21 -0400 (EDT)*References*: <200908210842.EAA13961@smc.vnet.net> <h6o73j$fsa$1@smc.vnet.net>*Reply-to*: HPR <read at math.uvm.edu>

Tomas Garza wrote: > > Number of combinations of n objects taken in sets of k, is that what you mean? > The answer to that is n!/k! (n-k)! > > The actual combinations carry in Mathematica the strange name of > KSubsets, and in order to calculate them you must FIRST call the > Combinatorica package: thus > > <<Combinatorica` > > KSubsets[{"A","B","C","D"},3] > {{A,B,C},{A,B,D},{A,C,D},{B,C,D}} There is no need to load a package for this. Use the built-in function Subsets. Subsets[{"A", "B", "C", "D"}, {3}] Also useful are the built-in functions Tuples and Permutations. -- Helen Read University of Vermont

**References**:**A Question about Combinatorica***From:*Marwa Abd El-Wahaab <m.a.elwahaab@gmail.com>