Re: pattern matching all list elements but last
- To: mathgroup at smc.vnet.net
- Subject: [mg54648] Re: pattern matching all list elements but last
- From: "Jens-Peer Kuska" <kuska at informatik.uni-leipzig.de>
- Date: Fri, 25 Feb 2005 01:18:47 -0500 (EST)
- Organization: Uni Leipzig
- References: <cvhgo5$r1p$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Hi, ls /. {a___, b_Integer} :> {Sequence @@ (100*{a}), b} ?? Regards Jens "Trevor Baca" <trevorbaca at gmail.com> schrieb im Newsbeitrag news:cvhgo5$r1p$1 at smc.vnet.net... > hi mathgroup folks, > > let's say ls looks like this: > > ls = {{1}, {2,3}, {4,5,6}, {7,8,9,10}} > > is there an elegant way to match all integers *except the last > (rightmost)* in each list and, say, add 100 to each? > > ls /. <magic replacement rule goes here> > > or > > ls //. <magic replacement rule goes here> > > to give {{1}, {102,3}, {104,105,6}, {107,108,109,10}}? > > this works: > > Release[ ls //. {a___, b_Integer, c___, z_Integer} :> {a, Hold[b + > 100], c, z} ] > > but is there a more elegant pattern, possibly one that avoids the > Hold-Release trick? > > > trevor. >