"NA-friendly" operator
On Oct 30, 2012, at 2:25 PM, Berend Hasselman wrote:
On 30-10-2012, at 22:08, vincent guyader wrote:
Hi everyone,
i'm looking for a "NA-friendly" operator
I explain :
vec<-c(3,4,5,NA,1,NA,9,NA,1)
vec[vec == 1] # NA 1 NA NA 1
I dont want the NA's :
vec[vec == 1 & ! is.na(vec)]# 1 1
is the same as
vec[vec %in% 1] # 1 1
%in% is NA-friendly :)
But if i want >2 without the NA's :
vec[vec>2] #3 4 5 NA NA 9 NA
if i dont want the NA i have to do :
vec[vec>2 & !is.na(vec)] #3 4 5 9
is there an op?rator to directly do that?
You could define one "%>.nona%" <- function(x,y) x[x>y & !is.na(vec)] and use vec %>.nona% 2 Use ?`%in%` to see an example (in the Examples section)
Don't need to define a new operator. %in% will work fine: vec<-c(3,4,5,NA,1,NA,9,NA,1) vec[vec %in% 1] (Seems a bit silly if you ask me. Using which would seem to provide more minforamtion.)
which(vec==1)
[1] 5 9
David Winsemius, MD Alameda, CA, USA