MathGroup Archive: January 2010 [00921]

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position of sequence of numbers in list

To: mathgroup at smc.vnet.net
Subject: [mg106976] position of sequence of numbers in list
From: JB <jkerrb at gmail.com>
Date: Sat, 30 Jan 2010 07:12:04 -0500 (EST)

Hi,

What is the most efficient way to find the position of the beginning
of a sequence of numbers from a list?

I found a couple of ways:

find 3,4 in list={1,2,3,4,5};

 1.   pos=Intersection[Position[list,3],(Position[list,4])+1]

 2.   pos=Position[Partition[list,2,1],{3,4}]

Are there other ways to do this?
What is the best way when dealing with large lists?

Thanks,
JB

Follow-Ups:
- Re: Re: position of sequence of numbers in list
  - From: Leonid Shifrin <lshifr@gmail.com>
- Re: position of sequence of numbers in list
  - From: Leonid Shifrin <lshifr@gmail.com>
- Re: position of sequence of numbers in list
  - From: Leonid Shifrin <lshifr@gmail.com>
- Re: position of sequence of numbers in list
  - From: Leonid Shifrin <lshifr@gmail.com>
- Re: position of sequence of numbers in list
  - From: DrMajorBob <btreat1@austin.rr.com>
- Re: position of sequence of numbers in list
  - From: Patrick Scheibe <pscheibe@trm.uni-leipzig.de>

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