Re: pattern matching and droping elements from list of lists.

*To*: mathgroup at smc.vnet.net*Subject*: [mg49775] Re: pattern matching and droping elements from list of lists.*From*: "Dr. Wolfgang Hintze" <weh at snafu.de>*Date*: Fri, 30 Jul 2004 06:02:27 -0400 (EDT)*References*: <ceargm$av9$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Define In[34]:= li = Outer[List, {a, b, c}, {a, b, c}, {a, b, c}]; Optional simplification of the list In[36]:= x = Flatten[li, 2]; Operation yielding what you wanted In[37]:= Complement[x, Select[x, Equal @@ #1 & ]] Out[37]= {{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, 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}} Checkinh lengths In[4]:= Length[x] Length[y] Out[4]= 27 Out[5]= 24 Regards, Wolfgang sean kim wrote: > hello group, > > Outer[List, {a, b, c}, {a, b, c}, {a, b, c}] > > will output > > {{ > {{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}} > }} > > how do I remove {a,a,a} and {b,b,b} and {c,c,c} from above? > > thanks all in advance for any insights > > sean > >