CODEWITHSUNDEEP
rsortingnatural-sort
DaniCee
DaniCee

Reputation: 3207

R: natural sort of elements in a vector, but certain value always last

Just trying to do a natural sort of a vector using gtools::mixedsort, but I want a certain value to always show up last... is there a clean way to do it? Or should I remove those values from the vector before sorting and then add them manually? Thanks!

In the MWE below I want "na" last:

> aa <- c("235dfh","na","addk20","vcxvz89dg","REni0","na","235dfh")
> gtools::mixedsort(unique(aa))
[1] "235dfh"    "addk20"    "na"        "REni0"     "vcxvz89dg"

Upvotes: 1

Views: 243

Answers (1)

Ronak Shah
Ronak Shah

Reputation: 389047

This is kind of hack : 

aa[aa == 'na'] <- NA
bb <- sort(unique(aa), na.last = TRUE)
bb
#[1] "235dfh"    "addk20"    "REni0"     "vcxvz89dg" NA

and then put the value back if needed. 

bb[is.na(bb)] <- 'na'
#[1] "235dfh"    "addk20"    "REni0"     "vcxvz89dg" "na"

Or using setdiff : 

c(sort(setdiff(aa, 'na')), 'na')

Upvotes: 2

Related Questions