[R] sapply(x, simplyfy = FALSE)

lapply_and_sapply.R

a <- data.frame(x = c(1, 2, 3), y = c(4, 5, 6), z = c(7, 8, 9))
b <- data.frame(x = c(1, 2, 3) * 2, y = c(4, 5, 6) * 2, z = c(7, 8, 9) * 3)
c <- data.frame(x = c(1, 2, 3) * 3, y = c(4, 5, 6) * 3, z = c(7, 8, 9) * 3)
l <- list(a = a, b = b, c = c)

x <- c("a", "b", "c")

get_df <- function(x){
  df <- l[[x]]
  return(df)
}

list_of_df <- lapply(x, get_df)
names(list_of_df)
# NULL
list_of_df
[[1]]
#   x y z
# 1 1 4 7
# 2 2 5 8
# 3 3 6 9

# [[2]]
#   x  y  z
# 1 2  8 21
# 2 4 10 24
# 3 6 12 27

# [[3]]
#   x  y  z
# 1 3 12 21
# 2 6 15 24
# 3 9 18 27

list_of_df_sapply <- sapply(x, get_df, simplify = FALSE, USE.NAMES = TRUE)
names(list_of_df_sapply)
# [1] "a" "b" "c"
list_of_df_sapply
$a
#   x y z
# 1 1 4 7
# 2 2 5 8
# 3 3 6 9

# $b
#   x  y  z
# 1 2  8 21
# 2 4 10 24
# 3 6 12 27

# $c
#   x  y  z
# 1 3 12 21
# 2 6 15 24
# 3 9 18 27