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RE: Pattern Matching in Lists

• To: mathgroup at smc.vnet.net
• Subject: [mg35557] RE: [mg35547] Pattern Matching in Lists
• From: "Harvey P. Dale" <hpd1 at nyu.edu>
• Date: Fri, 19 Jul 2002 06:07:58 -0400 (EDT)
• Sender: owner-wri-mathgroup at wolfram.com

Tony:
	This should do it:
Length[Select[Partition[w,2,1],#[[1]]==1&&#[[2]]==0&]]
	Best,
	Harvey
Harvey P. Dale
University Professor of Philanthropy and the Law
Director, National Center on Philanthropy and the Law
New York University School of Law
Room 206A
110 West 3rd Street
New York, N.Y. 10012-1074

-----Original Message-----
From: Anthony Mendes [mailto:amendes at zeno.ucsd.edu] 
To: mathgroup at smc.vnet.net
Subject: [mg35557] [mg35547] Pattern Matching in Lists

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


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