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Challenge: Fastest method to convert positive integers to 1 in a long list

• To: mathgroup at smc.vnet.net
• Subject: [mg52172] Challenge: Fastest method to convert positive integers to 1 in a long list
• From: "Carl K. Woll" <carlw at u.washington.edu>
• Date: Sat, 13 Nov 2004 04:40:26 -0500 (EST)
• Organization: University of Washington
• Sender: owner-wri-mathgroup at wolfram.com

Hi all,

Inspired by the recent thread on counting runs, I have the following 
challenge. Come up with a method to convert all the positive integers in a 
long sequence of nonnegative integers to 1, so that the sequence consists of 
only 0s and 1s. Let the sequence be given by

seq = Table[Random[Integer, 10], {10^6}];

Then, one technique is

newseq = 1+Quotient[#,#+1,1]&@seq;

Can anyone do better?

Carl Woll 

• Follow-Ups:
  • Re: Challenge: Fastest method to convert positive integers to 1 in a long list
    • From: János <janos.lobb@yale.edu>
  • Re:Re: Counting Runs
    • From: "Fred Simons" <f.h.simons@tue.nl>
  • Re: Challenge: Fastest method to convert positive integers to 1 in a long list
    • From: Selwyn Hollis <sh2.7183@misspelled.erthlink.net>
  • Re: Challenge: Fastest method to convert positive integers to 1 in a long list
    • From: Andrzej Kozlowski <akoz@mimuw.edu.pl>