[R] second element of a list

Greg Snow Greg.Snow at imail.org
Fri Oct 1 01:38:18 CEST 2010


Is the matrix the 1st or 2nd?  Your description does not seem consistent.

Here is one way to grab just the 2nd element from each sublist from a list:

lapply( mylist, '[[', 2 )

-- 
Gregory (Greg) L. Snow Ph.D.
Statistical Data Center
Intermountain Healthcare
greg.snow at imail.org
801.408.8111


> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-
> project.org] On Behalf Of Gregory Ryslik
> Sent: Thursday, September 30, 2010 5:35 PM
> To: R Help
> Subject: [R] second element of a list
> 
> 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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