[R] second element of a list

[Gregory Ryslik]

Thank you both for your help! I was interested in how to get at either element specifically. Your solutions work fine though. If I need the first element its lapply(thelist,'[[',1) and if I need the second its lapply(thelist,'[[',1).

Thanks again, you just saved me a slow for loop!

Kind regards,
Greg


On Sep 30, 2010, at 7:39 PM, Phil Spector wrote:

> Gregory -
>   I'm confused -- if the first element is the matrix you
> want, why would you use 2 as an index?
>   Here's a way to get a list with the first elements of each
> member of a list:
> 
>     lapply(thelist,'[[',1)
> 
> 					- Phil Spector
> 					 Statistical Computing Facility
> 					 Department of Statistics
> 					 UC Berkeley
> 					 spector at stat.berkeley.edu
> 
> 
> On Thu, 30 Sep 2010, Gregory Ryslik wrote:
> 
>> Hi,
>> 
>> I have a list of of n elements (where n is unknown beforehand). Each element of the list has two subelements. The first is a matrix, the second is a number. I want to make a list of just the matrices.
>> 
>> I want to do something like mylists[[ ,2]] but that obviously doesn't work. Is there a simple way to get around this?
>> 
>> Thanks!
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