Adding column if it does not exist
Solution 1:
Another option that does not require creating a helper function (or an already complete data.frame) using tibble's add_column:
library(tibble)
cols <- c(top_speed = NA_real_, nhj = NA_real_, mpg = NA_real_)
add_column(mtcars, !!!cols[setdiff(names(cols), names(mtcars))])
Solution 2:
We could create a helper function to create the column
fncols <- function(data, cname) {
add <-cname[!cname%in%names(data)]
if(length(add)!=0) data[add] <- NA
data
}
fncols(mtcars, "mpg")
fncols(mtcars, c("topspeed","nhj","mpg"))