Reaplace NA values from different columns - r

Question

R replace problem
Can't replace in the dataset NA values from different columns with a median of the same column with NA value.
Titanic.new is the dataset.
I have tried:
fun3<-function(x)
{
column.numeric<-x[,sapply(x,is.numeric)]
column.numeric[which(is.na(column.numeric))]<-median(column.numeric,na.rm = TRUE)
return(column.numeric)
}
fun3(titanic.new)
I'm getting an error:
Error in median.default(column.numeric, na.rm = TRUE) :
need numeric data
What am I doing wrong?

Answer 1

We can do some modification in the function. Loop through the columns of the dataset, find whether the type is numeric ('i1') -> return a logical vector. Subset the data using the vector, loop through the columns with lapply and replace the NAs in the column with the median of that column
fun3<-function(x){
i1 <- sapply(x,is.numeric)
x[i1] <- lapply(x[i1], function(y) replace(y, is.na(y), median(y, na.rm = TRUE)))
x
}
fun3(titanic.new)
Or it can be done with tidyverse
library(tidyverse)
titanic.new %>%
mutate_if(is.numeric, list(~ replace(., is.na(.), median(., na.rm = TRUE))))
which can be wrapped in a function as well
fun4 <- function(x) {
x %>%
mutate_if(is.numeric,
list(~ replace(., is.na(.), median(., na.rm = TRUE))))
}
Also, this can be done more compactly with na.aggregate
library(zoo)
i1 <- sapply(titanic.new, is.numeric)
titanic.new[i1] <- na.aggregate(titanic.new[i1], FUN = median)