Re: Pattern Matching in Lists
- To: mathgroup at smc.vnet.net
- Subject: [mg35556] Re: Pattern Matching in Lists
- From: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>
- Date: Fri, 19 Jul 2002 06:07:57 -0400 (EDT)
- Organization: Universitaet Leipzig
- References: <ah5qce$59o$1@smc.vnet.net>
- Reply-to: kuska at informatik.uni-leipzig.de
- Sender: owner-wri-mathgroup at wolfram.com
Hi, Count10Seqence[w_List] := Length[Cases[First /@ Split[w] //. { {a___, 1, 0, b__} :> {a, {1, 0}, b}, {a__, 1, 0} :> {a, {1, 0}}}, _List]] Regards Jens Anthony Mendes wrote: > > Hello, > > Suppose w={1,1,1,0,0,1,0,1,0,0,1,0,0}. > > How can I count the number of occurrences of a 1 in w immediately > followed by a 0 in w? > > I have tried every incarnation of Count[] I can think of; for example, > > Count[w,{___,1,0,___}] > > does not seem to work. In general, how can I count the number of > occurrences of a 1 followed by a 0 in a list of 1's and 0's? Thank you! > > -- > Tony > _____________________ > amendes at math.ucsd.edu