# [R] create list of vectors in for loop

Paul Sanfilippo prseye at gmail.com
Tue Dec 6 11:21:52 CET 2016

```Thank you Jim.

On 6 December 2016 at 9:17:21 pm, Jim Lemon (drjimlemon at gmail.com) wrote:

Hi Paul,
The easy to understand way is:

n <- c(1:10)
# Create empty list to store vectors
list_of_vecs <- list()

# Create n vectors of random numbers - length 10. This works ok.
for (i in n){
list_of_vecs[[i]]<-rnorm(10,0,1)
}

If you really want to use "assign":
for (i in n){
vecname<-paste('vec_', i, sep = '')
assign(vecname, rnorm(10,0,1))
list_of_vecs[[i]]<-get(vecname)
}

Jim

On Tue, Dec 6, 2016 at 8:44 PM, Paul Sanfilippo <prseye at gmail.com> wrote:
> Hi,
>
> As an exercise, I am trying to create a list of 10 random number vectors in a loop. I can create the vectors but am unsure how to assemble them in the list as part of the loop. Any advice?
>
>
> # Number of vectors to create
> n <- c(1:10)
>
> # Create empty list to store vectors
> list_of_vecs <- list()
>
> # Create n vectors of random numbers - length 10. This works ok.
> for (i in seq_along(n)){
> assign(paste('vec_', i, sep = ''), rnorm(10,0,1))
> }
>
> # But how do I append them in a list. This doesn’t work:
> for (i in seq_along(n)){
> list_of_vecs <- list(list_of_vecs,(assign(paste('vec_', i, sep = ''), rnorm(10,0,1))))
> }
>
>
> Thank you,
>
> Paul
>
>
>
> [[alternative HTML version deleted]]
>
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