Here are several approaches. The test data frame DF is defined in (1) and used in the other approaches as well.
1) dplyr - across/coalesce
library(dplyr)
# test data
DF <- data.frame(a = c(NA, NA, 1, 2), b = 1:4, c = letters[1:4])
DF %>%
mutate(across(where(is.numeric), ~ coalesce(., median(., na.rm = TRUE))))
giving:
a b c
1 1.5 1 a
2 1.5 2 b
3 1.0 3 c
4 2.0 4 d
2) dplyr/tidyr - across/replace_na
library(dplyr)
library(tidyr)
DF %>%
mutate(across(where(is.numeric), ~ replace_na(., median(., na.rm = TRUE))))
3) zoo - na.aggregate
library(zoo)
ok <- sapply(DF, is.numeric)
replace(DF, ok, na.aggregate(DF[ok], FUN = median))
4) Base R
na.median <- function(x) replace(x, is.na(x), median(x, na.rm = TRUE))
ok <- sapply(DF, is.numeric)
replace(DF, ok, lapply(DF[ok], na.median))
5) Base R - S3
na.median <- function(x, ...) UseMethod("na.median")
na.median.default <- identity
na.median.numeric <- function(x, ...) {
replace(x, is.na(x), median(x, na.rm = TRUE))
}
replace(DF, TRUE, lapply(DF, na.median))
6) magrittr We first make a copy of DF to avoid clobbering it -- although not recommend you can just use DF in last line if you are ok with overwriting it -- and use magrittr %<>%. na.median is from (4).
library(magrittr)
DF2 <- DF
DF2[sapply(DF2, is.numeric)] %<>% lapply(na.median)
7) collapse - ftmv ftmv or its synonym ftransformv provide a compact expression. This uses na.median is from (4).
library(collapse)
tfmv(DF, is.numeric, na.median)
