Use a for loop to rename variables in data frames - r

Question

I have the following data which I have split by name into separate data frames. After I run the following code, the variables in each data set are automatically named "X..i..".
I would like to rename the variable of each separate data frame so it matches the data set.
# load data
df1_raw <- data.frame(name = c("A", "B", "C", "A", "C", "B"),
start = c(1, 3, 4, 5, 2, 1),
end = c(6, 5, 7, 8, 6, 7))
df1 <- split(x = df1_raw, f = df1_raw$name) # split data by name
df1 <- lapply(df1, function(x) Map(seq.int, x$start, x$end)) # generate sequence intervals
df1 <- map(df1, unlist) # unlist sequences
df1 <- lapply(df1, data.frame) # convert to df
# rename variables
name <- c("A", "B", "C")
for (i in seq_along(df1)) {
names(df1[i]) <- name[i]
}
The last for loop does not work to rename variables. When I type names(df1$A) I still get "X..i..". The output I would like from names(df1$A) is "A".
Does anyone have any thoughts on how to rename these variables? Thanks!

Answer 1

You need to use [[]] when indexing from a list
for (i in seq_along(df1)) {
names(df1[[i]]) <- name[i]
}
Alternatively you could change how you create the list so you don't have to rename after the fact
df1 <- split(x = df1_raw, f = df1_raw$name) # split data by name
df1 <- lapply(df1, function(x) Map(seq.int, x$start, x$end)) # generate sequence intervals
df1 <- map(df1, unlist) # unlist sequences
df1 <- Map(function(x,name) {as.data.frame(setNames(list(x), name))}, df1, names(df1))

Answer 2

I think the solution by #MrFlick is enough for addressing the issue of renaming within a for loop.
Here is a base R workaround that may work for you
lapply(
split(df1_raw, df1_raw$name),
function(x) {
with(
x,
setNames(
data.frame(unlist(mapply(seq, start, end))),
unique(name)
)
)
}
)
which gives
$A
A
1 1
2 2
3 3
4 4
5 5
6 6
7 5
8 6
9 7
10 8
$B
B
1 3
2 4
3 5
4 1
5 2
6 3
7 4
8 5
9 6
10 7
$C
C
1 4
2 5
3 6
4 7
5 2
6 3
7 4
8 5
9 6