Re: Building clusters out of a nested list

*To*: mathgroup at smc.vnet.net*Subject*: [mg114969] Re: Building clusters out of a nested list*From*: Bob Hanlon <hanlonr at cox.net>*Date*: Fri, 24 Dec 2010 04:13:57 -0500 (EST)*Reply-to*: hanlonr at cox.net

Using capital letters will conflict with built-in names (e.g., E). {{a, b, c}, {c, d}, {e, f}, {f, h}} //. {s___, t1 : {___, x_, ___}, m___, t2 : {___, x_, ___}, e___} :> {s, Union[t1, t2], m, e} {{a, b, c, d}, {e, f, h}} Bob Hanlon ---- Dmitry <dpesin at gmail.com> wrote: ============= Dear All, please, help me find a solution to the following problem: suppose I have a list of the form { {A,B,C},{C,D},{E,F},{F,H}}. I need to build a list whose entries are unions of all entries of the original list with nonzero intersection. For the example above, the end result is {{A,B,C,D},{E,F,H}}. Thanks a lot!