How do I combine data frames in a dataset that is a list, to create one full dataset?

Question

I have a dataset which is a list containing 1000 items that are data frames. I want to unlist these data frames using a loop such that the end result is one large data frame with each element of the data set stacked upon one another. I've made a jovial example below:

list1 <- data.frame(x = c("hello","bye"), y = c(1, 4), z = c(TRUE, FALSE)) 
list2 <- data.frame(x = c("bye","hello"), y = c(5, 8), z = c(FALSE, FALSE)) 
fulllist <- list(list1, list2)

As mentioned above I'm wanting to make 'fulllist' into a data frame using a loop as seen below. Thanks in advance

x	y	z
hello	1	TRUE
bye	4	FALSE
bye	5	FALSE
hello	8	FALSE

Does this answer your question? [Combine two data frames by rows (rbind) when they have different sets of columns](https://stackoverflow.com/questions/3402371/combine-two-data-frames-by-rows-rbind-when-they-have-different-sets-of-columns) — harre, Jun 09 '22 at 16:25
@harre, thanks for looking, I believe it does. akrun's comment also works well too :) — Luke Robins, Jun 09 '22 at 16:31

Andrea M · Answer 1 · 2022-06-09T16:30:09.130

0

bind_rows from dplyr can take a list of dataframes as input:

dplyr::bind_rows(fulllist)

edited Jun 09 '22 at 16:30

answered Jun 09 '22 at 16:24

Andrea M

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Is there a quicker way to do this when you have 1000 elements in the dataset rather than type list1, list2, list3... list1000 – Luke Robins Jun 09 '22 at 16:27
While it would be preferable for you not to have 1000 individual data frames to begin with; if you have this might save you some time: https://stackoverflow.com/questions/41811675/rbind-data-frames-based-on-a-common-pattern-in-data-frame-name – harre Jun 09 '22 at 16:32

score 0 · Answer 2 · answered Jun 09 '22 at 16:35

You should not really be handling that many data frames though, but here's a possible solution given that you have list1, list2 and so on ...

list1 <- data.frame(x = c("hello","bye"), y = c(1, 4), z = c(TRUE, FALSE)) 
list2 <- data.frame(x = c("bye","hello"), y = c(5, 8), z = c(FALSE, FALSE))

Select all data frames

lists <- mget(ls(pattern = "list"))

$list1
      x y     z
1 hello 1  TRUE
2   bye 4 FALSE

$list2
      x y     z
1   bye 5 FALSE
2 hello 8 FALSE

Combine them into one

do.call(rbind, lists) %>% 
  tibble()

# A tibble: 4 x 3
  x         y z    
  <chr> <dbl> <lgl>
1 hello     1 TRUE 
2 bye       4 FALSE
3 bye       5 FALSE
4 hello     8 FALSE

How do I combine data frames in a dataset that is a list, to create one full dataset?

2 Answers2