How to conditionally fill a cell based on two conditions in R using dplyr

I’ve done this in Base a bunch by manually entering the conditions that need to be met in order to set a new value of a new cell, but I really want to automate the process using dplyr.

This is the problem I currently have:
I have about 50 different places (only 3 in the code below), each with their own distance. I want to be able to set a segment value (Lets say ‘a’ ‘b’ or ‘c’) based on the values in the place and distance column. Note that there are repeating distance values.

DF <- data.frame(place = c(rep('x',10), rep('y', 5), rep('z',5)), distance = c(0:9,5:9,5:9), segment = rep(NA,20))

So, if something is at place ‘x’ and is above 0, it will have segment ‘a’. If something is at place ‘y’ and is above 5, it will have segment ‘b’. Places ‘z’ above 5 will have segment ‘c.’

In Base R, I would do this like this:
DF$segment[DF$place == 'x' & DF$distance > 0] <- 'a'

I just want to know if there was a dplyr way to do it.

>Solution :

This should work:

DF %>% 
  mutate(segment = case_when((place == "x" & distance > 0) ~ "a",
                             (place == "y" & distance > 5) ~ "b",
                             (place == "z" & distance > 5) ~ "c",
                             .default = "NA"))

If there is no match it will fill it up with NA. You can change that if you want.