subset list based on logical within element flag

names(which(my_list == 'Fred'))

-----Original Message-----
From: r-help-bounces at r-project.org 
[mailto:r-help-bounces at r-project.org] On Behalf Of Srinivas Iyyer
Sent: Wednesday, March 12, 2008 6:53 PM
To: Benilton Carvalho; mwkimpel at gmail.com
Cc: R Help
Subject: Re: [R] subset list based on logical within element flag

Hi I have the smililar question.

I have a list:
my_list <- list(name="Fred", wife="Mary", no.children=3, 
child.ages=c(4,7,9)) 

my_list

$name
[1] "Fred"

$wife
[1] "Mary"

$no.children
[1] 3

$child.ages
[1] 4 7 9


Now I want to search "Fred" and get attribute of that value 
which is 'name'. 

how do I get it. 

match(my_list,"Fred")

[1]  1 NA NA NA

my thinking stops right here... 

list operations in R is too tough to digest and there is not 
good documentations. 

Could any one please help. 

thanks
Srini







--- Benilton Carvalho <bcarvalh at jhsph.edu> wrote:

gene.pair.tf.lst[sapply(gene.pair.tf.lst, "[[", "sig.cor")]

b


On Mar 12, 2008, at 5:24 PM, Mark W Kimpel wrote:

I have a very long list that I'd like to subset

based on a logical

value
within each element. Example below. I'd like to

get just those list

elements for further study whose $sig.cor slot is

TRUE. In this

example,
I'd only want element [[2]].

Should be simple, I know. How can I do this?

Thanks, Mark

gene.pair.tf.lst

[[1]]
[[1]]$gene.pair
[1] "Lgals1:Pxmp2"

[[1]]$sig.cor
[1] FALSE


[[2]]
[[2]]$gene.pair
[1] "Lgals1:Pxmp2"

[[2]]$sig.cor
[1] TRUE


[[3]]
[[3]]$gene.pair
[1] "Lgals1:Pxmp2"

[[3]]$sig.cor
[1] FALSE
--

Mark W. Kimpel MD  ** Neuroinformatics ** Dept. of

Psychiatry

Indiana University School of Medicine

15032 Hunter Court, Westfield, IN  46074

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