Loading multiple .RData and binding into a single data.frame

Question

I have multiple .RData in a folder. I can load them as follows:

df1 <- data.frame(X = 1:10)
df2 <- data.frame(X = 1:10)

save(df1, file = "df1.RData", compress = "xz")
save(df2, file = "df2.RData", compress = "xz")

rm(list = ls())

load("df1.RData")
load("df2.RData")

and bind them using bind_rows function from dplyr as

library(tidyverse)
bind_rows(df1, df2)

I wonder if it is possible to load all files and bind them something like this

list.files(
      path      = "."
    , pattern    = "*.RData"
    , full.names = TRUE
    )  %>%
  map_dfr(.x = ., .f = ~load(file = .x))

Answer 1

You could use get() to return the data from the calling environment or alternatively load them into a new environment and bind them afterwards. Note that .Rdata files can contain multiple objects but assuming these objects are all conformable, you could do:

library(purrr)
library(dplyr)

df1 <- data.frame(X = 1:10)
df2 <- data.frame(X = 1:10)

save(df1, file = "df1.RData", compress = "xz")
save(df2, file = "df2.RData", compress = "xz")

list.files(pattern = "\\.RData$") %>%
   map_df(~ get(load(file = .x)))

    X
1   1
2   2
3   3
4   4
5   5
6   6
7   7
8   8
9   9
10 10
11  1
12  2
13  3
14  4
15  5
16  6
17  7
18  8
19  9
20 10 

Or:

temp_env <- new.env()

list.files(pattern = "\\.RData$")  %>%
  map(~load(file = .x, envir = temp_env)) 

bind_rows(as.list(temp_env))