Re: position of sequence of numbers in list
- To: mathgroup at smc.vnet.net
- Subject: [mg107005] Re: [mg106976] position of sequence of numbers in list
- From: Bob Hanlon <hanlonr at cox.net>
- Date: Sun, 31 Jan 2010 05:58:00 -0500 (EST)
- Reply-to: hanlonr at cox.net
Position[list, Sequence[3, 4]]
Bob Hanlon
---- JB <jkerrb at gmail.com> wrote:
=============
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