Re: List Comparison
- To: mathgroup at smc.vnet.net
- Subject: [mg67169] Re: List Comparison
- From: Peter Pein <petsie at dordos.net>
- Date: Sun, 11 Jun 2006 02:17:57 -0400 (EDT)
- References: <e6e2b7$1uc$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
LectorZ schrieb: > Dear experts, > > I want to compare two lists containing sublists and make out of them 3 > result lists. > The comparison applies to the first two elements of the sublists. > > list1 = {{1, aa, 565}, {1, bb, 566}, { > 1, cc, 546}, {2, dd, 56}, {2, ff, 56}, {2, ss, 5}} > list2 = {{1, aa, > 34}, {1, bb, 66}, {1, cc, 5443}, {2, dd, 76}, {2, ff, 87}, {2, mm, > 87}} > > Result ONE should be: > > If the FIRST element AND the SECOND elements of the sublists are equal, > then prepend the THIRD elements from list2. > > result1={{1, aa, 565, 34}, {1, bb, 566, 66}, { > 1, cc, 546, 5443}, {2, dd, 56, 76}, {2, ff, 56, 87}} > > Result TWO should be: > the FIRST element OR the SECOND elements of the sublists are NOT equal, > then display the difference from the list1 perspective > > result2={{2, ss, 5}} > > Result THREE should be: > the FIRST element OR the SECOND elements of the sublists are NOT equal, > then display the difference from the list2 perspective > result3={{2, mm, 87}} > > Thanks for your help > > LZ > list1 = {{1, aa, 565}, {1, bb, 566}, {1, cc, 546}, {2, dd, 56}, {2, ff, 56}, {2, ss, 5}}; list2 = {{1, aa, 34}, {1, bb, 66}, {1, cc, 5443}, {2, dd, 76}, {2, ff, 87}, {2, mm, 87}}; res1 = Flatten[(Cases[list1, l1:Append[Take[#1, 2], _] :> Append[l1, Last[#1]]] & ) /@ list2, 1] --> {{1, aa, 565, 34}, {1, bb, 566, 66}, {1, cc, 546, 5443}, {2, dd, 56, 76}, {2, ff, 56, 87}} st[l1_, l2_] := Take[l1, 2] === Take[l2, 2]; res2 = Complement[list1, list2, SameTest -> st] --> {{2, ss, 5}} res3 = Complement[list2, list1, SameTest -> st] --> {{2, mm, 87}} hth, Peter