[R] How to convert a list to a matrix

[Romain Francois]

Le 03.02.2005 16:42, Romain Francois a écrit :

> Hello,
>
> try the following :
>
>> l <- list(NULL)
>> l[[1]] <- 1:2
>> l[[2]] <- 2:3
>> l[[3]] <- 4:5
>> l
>
> [[1]]
> [1] 1 2
>
> [[2]]
> [1] 2 3
>
> [[3]]
> [1] 4 5
>
>> matrix(unlist(l),ncol=2)
>
Sorry, i forgot the byrow argument, the correct comand was :

matrix(unlist(l),ncol=2,byrow=T)

I need some coffee. :-)

Romain

>     [,1] [,2]
> [1,]    1    3
> [2,]    2    4
> [3,]    2    5
>
>
> Is that what you want ?
>
> Romain
> Le 03.02.2005 16:08, michael watson (IAH-C) a écrit :
>
>> Hi
>>
>> Sorry to ask such a basic question.  I have a list, each element of
>> which is a vector of two values.  What I actually want is a matrix with
>> two columns, and one row per element of the list.  Obviously I have
>> tried as.matrix(), and as.vector() but I didn't expect the latter to
>> work.
>>
>> I feel so lame asking this.  Any suggestions?
>>
>> Mick
>>
>>  
>>
>


-- 
Romain FRANCOIS : francoisromain at free.fr
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