Re: Combinations

*To*: mathgroup at smc.vnet.net*Subject*: [mg49719] Re: Combinations*From*: BobHanlon at aol.com*Date*: Thu, 29 Jul 2004 07:43:45 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

Needs["DiscreteMath`Combinatorica`"]; Strings[{a,b,c}, 3] {{a, a, a}, {a, a, b}, {a, a, c}, {a, b, a}, {a, b, b}, {a, b, c}, {a, c, a}, {a, c, b}, {a, c, c}, {b, a, a}, {b, a, b}, {b, a, c}, {b, b, a}, {b, b, b}, {b, b, c}, {b, c, a}, {b, c, b}, {b, c, c}, {c, a, a}, {c, a, b}, {c, a, c}, {c, b, a}, {c, b, b}, {c, b, c}, {c, c, a}, {c, c, b}, {c, c, c}} %==Flatten[Outer[List,{a,b,c},{a,b,c},{a,b,c}],2] True Length[%%] 27 Bob Hanlon > In a message dated Tue, 27 Jul 2004 11:17:25 +0000 (UTC), < > gregory.lypny at videotron.ca> writes: Does Mathematica have a built-in function that > will generate a simple > list all possible combinations of a list of strings? For example, > {a,b,c}, where the elements are strings, should give 3x3=27 triplets of > "aaa", "aba", etc. > > I tried > > In[4]:=Outer[{a,b,c},{a,b,c},{a,b,c}] > > but I get > > {{{a, b, c}[a, a], {a, b, c}[a, b], { > a, b, c}[a, c]}, {{a, b, c}[b, a], {a, b, c}[b, b], {a, b, > c}[b, c]}, {{a, b, c}[c, a], {a, b, c}[c, b], {a, b, c}[c, c]}} > > which is going to be difficult to match with my data using BinCounts > and the like. >