Re: Partition a list into sublists of unequal size
- To: mathgroup at smc.vnet.net
- Subject: [mg83933] Re: [mg83919] Partition a list into sublists of unequal size
- From: Sseziwa Mukasa <mukasa at jeol.com>
- Date: Wed, 5 Dec 2007 07:04:20 -0500 (EST)
- References: <200712040929.EAA17852@smc.vnet.net>
On Dec 4, 2007, at 4:29 AM, antf wrote:
> Hello,
>
> I have a list that looks like the following:
>
> list={1,0,0,1,0,0,1,1,0,1,0,0,0,0,1,0}
>
> I then find the positions of the 1s in the list:
>
> positions = Flatten@Position[list,1]
>
> {1,4,7,8,10,15}
>
> I then want to partition a third list into sublists so that the first
> sublist is from index 1;;1, the second sublist is from index 2;;4, the
> third sublist is from index 5;;7, the fourth sublist is just element
> 8, etc.
>
> Currently, I use Partition on the positions sublist with overlap as
> in:
>
> Partition[Join[{1},positions],2,1]
>
> {{1,1},{1,4},{4,7},{7,8},{8,10},{10,15}}
>
> I then use this list to partition the target list by Mapping Take to
> each element of this list and adjusting the first index appropriately.
>
> I am sure there must be a simpler way to do this. Can anyone tell me
> how to do this operation?
I'm not sure about simple, but here's my approach
list[[Range[#[[1]]+1,#[[2]]]]]]&/@Partition[Prepend[positions,0],2,1]
Regards,
Ssezi
- References:
- Partition a list into sublists of unequal size
- From: antf <anthonyfox@gmail.com>
- Partition a list into sublists of unequal size