R help - Aug 2007 - Problem of vocabulary : retrieve element of a list of a list

Hi,

I read the posts for 2 hours and ?list and tried many comninations but I
haven't found the answer to this basic question. So I decided to post my
question even if it is a silly one ...

What is the instruction to retrieve, for example, the "D" of the first
list
?
Thanks in advance,
Ptit Bleu.

> x<-list(LETTERS[1:5], LETTERS[10:20])
> x
[[1]]
[1] "A" "B" "C" "D" "E"

[[2]]
 [1] "J" "K" "L" "M" "N"
"O" "P" "Q" "R" "S"
"T"

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x[[1]][4]

On 8/31/07, Ptit_Bleu <ptit_bleu at yahoo.fr>
wrote:
> Hi,
>
> I read the posts for 2 hours and ?list and tried many comninations but I
> haven't found the answer to this basic question. So I decided to post
my
> question even if it is a silly one ...
>
> What is the instruction to retrieve, for example, the "D" of the
first list
> ?
> Thanks in advance,
> Ptit Bleu.
>
>
> > x<-list(LETTERS[1:5], LETTERS[10:20])
> > x
> [[1]]
> [1] "A" "B" "C" "D" "E"
>
> [[2]]
>  [1] "J" "K" "L" "M" "N"
"O" "P" "Q" "R" "S"
"T"
>
> --
> View this message in context:
http://www.nabble.com/Problem-of-vocabulary-%3A-retrieve-element-of-a-list-of-a-list-tf4358872.html#a12422479
> Sent from the R help mailing list archive at Nabble.com.
>
> ______________________________________________
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> PLEASE do read the posting guide
http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
>

-- 
Felix Andrews / ???
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On 2007-August-31  , at 10:17 , Ptit_Bleu wrote:
>> x<-list(LETTERS[1:5], LETTERS[10:20])
not sure to have understood exactly what you meant.
if you want to search for the D in the list:
	lapply(x,charmatch,"D")
should get you started.

if you just want to know the syntax to extract an element from a list
	x[[1]][4]
will get you the "D". but I a sure you would have found out if you  
read the manual carefully.

maybe you should read an R introduction and practice on the examples  
there rather than go straight into your own data. It would take a  
week at most and is very rewarding in the long term.
An introduction in english:
	http://cran.r-project.org/doc/manuals/R-intro.pdf
A nice one in French
	http://www.cran.r-project.org/doc/contrib/Paradis-rdebuts_fr.pdf

Cheers,

JiHO
---
http://jo.irisson.free.fr/