Re: I NEED HELP WITH THIS

*To*: mathgroup at smc.vnet.net*Subject*: [mg35246] Re: [mg35208] I NEED HELP WITH THIS*From*: Tomas Garza <tgarza01 at prodigy.net.mx>*Date*: Wed, 3 Jul 2002 05:16:04 -0400 (EDT)*References*: <200207020612.CAA22319@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

One immediate possibility, though it could be improved, is as follows. First, I assume that your slashes, as in a1-a2, actually mean some sort of link, like in {a1, a2}, and not a minus sign. Then, first construct your elements properly: In[1]:= let = ToString /@ {a, b, c, d, e, f, g, h, i, j, k, l, m, n, o} Out[1]= {"a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o"} In[2]:= num = ToString /@ {1, 2} Out[2]= {"1", "2"} In[3]:= pairs = Outer[StringJoin, let, num] Out[3]= {{"a1", "a2"}, {"b1", "b2"}, {"c1", "c2"}, {"d1", "d2"}, {"e1", "e2"}, {"f1", "f2"}, {"g1", "g2"}, {"h1", "h2"}, {"i1", "i2"}, {"j1", "j2"}, {"k1", "k2"}, {"l1", "l2"}, {"m1", "m2"}, {"n1", "n2"}, {"o1", "o2"}} In[4]:= elem = Flatten[pairs] Out[4]= {"a1", "a2", "b1", "b2", "c1", "c2", "d1", "d2", "e1", "e2", "f1", "f2", "g1", "g2", "h1", "h2", "i1", "i2", "j1", "j2", "k1", "k2", "l1", "l2", "m1", "m2", "n1", "n2", "o1", "o2"} Then you get your triplets using In[5]:= Select[Partition[Flatten[Outer[List, pairs, elem, 1]], 3], #1[[1]] != #1[[2]] != #1[[3]] & ] (output omitted). Tomas Garza Mexico City ----- Original Message ----- From: "Said Neder" <neder at dominicanrepublic.com> To: mathgroup at smc.vnet.net Subject: [mg35246] [mg35208] I NEED HELP WITH THIS > Im developing some project and i need advice from > mathematics experienced dudes... please let me know. ... this is the issue: > > i have 30 variables connected in pairs.. so i have 15 pairs .. some thing > like: > > a1-a2 , b1-b2, c1-c2, d1-d2, e1-e2, f1-f2, g1-g2, h1-h2, i1-i2, j1-j2, > k1-k2, l1-l2,m1-m2,n1-n2,oi-o2 > > i need to generete as many 3 variables chains posibilities without repeating > variables or including variables of > same pair. > > some thing like > > a1-b1-c1 > > > any one has any idea?.. i need a formula for that.. i know this might be > easy for experienced mathematicians > >

**References**:**I NEED HELP WITH THIS***From:*"Said Neder" <neder@dominicanrepublic.com>