# [R] changing the number of elements in a list

09wkj Bill.K.Jannen at williams.edu
Wed Jun 9 15:59:35 CEST 2010

```I might give this a try as well:

my.list <- replicate(3, matrix(0, ncol=3, nrow=3), simplify=FALSE)

----
args(replicate)
function (n, expr, simplify = TRUE)

> replicate(3, matrix(0, ncol=3, nrow=3), simplify=FALSE)
[[1]]
[,1] [,2] [,3]
[1,]    0    0    0
[2,]    0    0    0
[3,]    0    0    0

[[2]]
[,1] [,2] [,3]
[1,]    0    0    0
[2,]    0    0    0
[3,]    0    0    0

[[3]]
[,1] [,2] [,3]
[1,]    0    0    0
[2,]    0    0    0
[3,]    0    0    0

> is.list(replicate(3, matrix(0, ncol=3, nrow=3), simplify=FALSE))
[1] TRUE
----

Bill

On Jun 9, 2010, at 9:54 AM, Ivan Calandra wrote:

> Hi,
>
> my.list <- vector(mode="list", length=number_of_matrices)
> ?
>
> HTH,
> Ivan
>
> Le 6/9/2010 15:46, Luis Borda de Agua a écrit :
>> I would like to have a list where each element is a matrix, for example:
>>
>> my.list<- list(matrix(0, ncol=3, nrow=3),
>>                        matrix(0, ncol=3, nrow=3),
>>                        matrix(0, ncol=3, nrow=3))
>>
>> The problem is, I would like to be able to change automatically the number of elements in the list (not only three as in the above example).
>>
>> That is, the instruction creating the list would be a part of a function that has an inputing parameter stating how many elements (matrices) the list has.
>>
>> I have tried several things, but none worked.
>> However, this seems to be a rather simple problem.
>> All help is welcome!
>>
>> LBA
>>
>> ______________________________________________
>> R-help at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-help
>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
>
> --
> Ivan CALANDRA
> PhD Student
> University of Hamburg
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> ivan.calandra at uni-hamburg.de
>
> **********
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