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r - append list to a list

I know this is a really noob question, but how do I append a list of dataframes to a dataframe to form a new list, with all the data.frames at the same level in the list?

Some of my attempts:

> df <- data.frame(time=1:5)
> df
  time
1    1
2    2
3    3
4    4
5    5
> innerlist <- list(df,df,df)
> innerlist
[[1]]
  time
1    1
2    2
3    3
4    4
5    5

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

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

> outerlist <- list(df,innerlist)
> outerlist
[[1]]
  time
1    1
2    2
3    3
4    4
5    5

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

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

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


> outerlist2 <- c(df,innerlist)
> outerlist2
$time
[1] 1 2 3 4 5

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

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

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

> outerlist3 <- cbind(df,innerlist)
> outerlist3
  time time time time
1    1    1    1    1
2    2    2    2    2
3    3    3    3    3
4    4    4    4    4
5    5    5    5    5

Pretend that all the dfs are different data-frames.

I want to append df to innnerlist, and get a list with 4 dfs, like:

> outerlistmagic <- magic( df, innerlist )
> outerlistmagic
[[1]]
  time
1    1
2    2
3    3
4    4
5    5

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

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

[[4]]
  time
1    1
2    2
3    3
4    4
5    5
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1 Reply

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by (71.8m points)

If you want df to be a list element, you have to wrap it in list because a data.frame is a list internally. For example:

append(list(df), innerlist)
c(list(df), innerlist)

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