Re: Any ideas on expanded results for SetPartitions in discrete-combinatoria
- To: mathgroup at smc.vnet.net
- Subject: [mg67062] Re: Any ideas on expanded results for SetPartitions in discrete-combinatoria
- From: Peter Pein <petsie at dordos.net>
- Date: Thu, 8 Jun 2006 04:53:55 -0400 (EDT)
- References: <e66600$n62$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Ike schrieb: > Looking for suggestions... > > SetPartitions drops partitions that have "overlaps", any ideas on how to > modify or recreate a SetPartitions function that doesn't drop these? > > For example > > SetPartitions[{A,B,C}] > > Generates: > > > {{{A, B, C}}, {{A}, {B, C}}, {{A, B}, {C}}, {{A, C}, {B}}, {{A}, {B}, {C}}} > > > What it is missing (for my needs) are the following: > > {{A,B}, {B, C}}, {{A,C}, {B, C}}, {{A,B}, {A, C}}, {{A,B}, {B, C},{A,C}} > > I have tried doing this: > > SetPartitions[{A,A,B,B,C,C}] which adds them but then I need a quick way > to delete the subsets that have duplicate elemenets. > > > Either way will get me where I need to be. But I can not figure it out. > > Thanks in advance for any help. > > Ike > wde at pdx.edu > Hi Ike, does In[1]:= Map[Union, SetPartitions[{A, A, B, B, C, C}], {0, 2}] Out[1]= {{{A, B, C}}, {{A}, {B, C}}, {{A}, {A, B, C}}, {{B}, {A, C}}, {{B}, {A, B, C}}, {{C}, {A, B}}, {{C}, {A, B, C}}, {{A, B}, {A, C}}, {{A, B}, {B, C}}, {{A, B}, {A, B, C}}, {{A, C}, {B, C}}, {{A, C}, {A, B, C}}, {{B, C}, {A, B, C}}, {{A}, {B}, {C}}, {{A}, {B}, {A, C}}, {{A}, {B}, {B, C}}, {{A}, {B}, {A, B, C}}, {{A}, {C}, {A, B}}, {{A}, {C}, {B, C}}, {{A}, {C}, {A, B, C}}, {{A}, {A, B}, {B, C}}, {{A}, {A, C}, {B, C}}, {{A}, {B, C}, {A, B, C}}, {{B}, {C}, {A, B}}, {{B}, {C}, {A, C}}, {{B}, {C}, {A, B, C}}, {{B}, {A, B}, {A, C}}, {{B}, {A, C}, {B, C}}, {{B}, {A, C}, {A, B, C}}, {{C}, {A, B}, {A, C}}, {{C}, {A, B}, {B, C}}, {{C}, {A, B}, {A, B, C}}, {{A, B}, {A, C}, {B, C}}, {{A}, {B}, {C}, {A, B}}, {{A}, {B}, {C}, {A, C}}, {{A}, {B}, {C}, {B, C}}, {{A}, {B}, {C}, {A, B, C}}, {{A}, {B}, {A, C}, {B, C}}, {{A}, {C}, {A, B}, {B, C}}, {{B}, {C}, {A, B}, {A, C}}} give the desired result? Peter