I have data as follows:
dat <- structure(
list(
freq = list(a= c(5, 38, 43, 27, 44, 20, 177), b=c(3, 5, 12, 53, 73))),
row.names = c(NA, -2L), class = "data.frame")
I would like to do two things:
- Remove the last item of each list
- Append the string values
"Infinity"
and"SUM"
Normally one could do
x <- c(1,2,3)
x <- x[-length(x)]
x <- append(x, c("Infinity", "SUM"))
But how does that work if these vectors are in a list?
Desired output:
dat_out <- structure(
list(
freq = list(a= c(5, 38, 43, 27, 44, 20, "Infinity", "SUM"), b=c(3, 5, 12, 53, "Infinity", "SUM"))),
row.names = c(NA, -2L), class = "data.frame")
CodePudding user response:
You can use lapply
:
dat$freq <- lapply(dat$freq, \(x){
x <- x[-length(x)]
x <- append(x, c("Infinity", "SUM"))
x
})`
# freq
# 1 5, 38, 43, 27, 44, 20, Infinity, SUM
# 2 3, 5, 12, 53, Infinity, SUM
CodePudding user response:
Using map
with mutate
library(dplyr)
library(purrr)
dat %>%
mutate(freq = map(freq, ~ c(.x[-n()], "Infinity", "SUM")))
freq
1 5, 43, 27, 44, 20, 177, Infinity, SUM
2 3, 12, 53, 73, Infinity, SUM
CodePudding user response:
Another option via the purrr
package:
library(dplyr)
dat %>%
purrr::pmap(~c(.x)) %>%
purrr::map(~.x %>%
head(-1) %>%
append(c("Infinity", "SUM")))