R help - Nov 2009 - where is a value in my list

I heve got a list: 

lista=list() 
a=c(2,4,5,5,6) 
b=c(3,5,4,2) 
c=c(1,1,1,8) 
lista[[1]]=a 
lista[[2]]=b 
lista[[3]]=c

 > lista 
[[1]] 
[1] 2 4 5 5 6 

[[2]] 
[1] 3 5 4 2 

[[3]] 
[1] 1 1 1 8 

I would like to know where is number 5 (which line)?

For example I have got a loop:

  k= vector(mode = "integer", length = 3)

 for(i in 1:3)
{
 for (j in 1:length(lista[[i]])){
if ((lista[[i]][j])==5   k[i]= [i])
}
}

This loop is wrong but I would like to get in my vector k sth like this:

k = lista[[1]][1], lista[[2]][1]     ...or sth similar
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On Nov 15, 2009, at 10:01 AM, Grzes wrote:
>
> I heve got a list:
>
> lista=list()
> a=c(2,4,5,5,6)
> b=c(3,5,4,2)
> c=c(1,1,1,8)
> lista[[1]]=a
> lista[[2]]=b
> lista[[3]]=c
>
>> lista
> [[1]]
> [1] 2 4 5 5 6
>
> [[2]]
> [1] 3 5 4 2
>
> [[3]]
> [1] 1 1 1 8
>
> I would like to know where is number 5 (which line)?
>
> For example I have got a loop:
>
>  k= vector(mode = "integer", length = 3)
>
> for(i in 1:3)
> {
> for (j in 1:length(lista[[i]])){
> if ((lista[[i]][j])==5   k[i]= [i])
> }
> }
>
> This loop is wrong but I would like to get in my vector k sth like  
> this:
>
> k = lista[[1]][1], lista[[2]][1]     ...or sth similar
I am a bit confused, since clearly lista[[1]][1] does _not_ == 5. It's  
also unclear what type of output you expect ... character, list,  
numeric?

See if these take you any further to your vaguely expressed goal:

 > lapply(lista, "%in%", 5)
[[1]]
[1] FALSE FALSE  TRUE  TRUE FALSE

[[2]]
[1] FALSE  TRUE FALSE FALSE

[[3]]
[1] FALSE FALSE FALSE FALSE

 > lapply(lista, function(x) which(x == 5) )
[[1]]
[1] 3 4

[[2]]
[1] 2

[[3]]
integer(0)
> --

David Winsemius, MD
Heritage Laboratories
West Hartford, CT