CODEWITHSUNDEEP
rdplyr
kismsu
kismsu

Reputation: 1099

What function should return to dplyr::do() to skip the case

I'm applying user defined function in do(), but for some cases I don't need to do a calculation (to catch log(<0)). What should my function return? NULL nor () doesn't help.

my_function<-function(data) {
    if(data$a<0) {
       return(NULL) #?????????
    } else {
       return(data.frame(ln=log(data$a)))
    }
}

table<-data.frame(a=seq(10,-10,by=-1),b=seq(0,20,by=1))

result<-table %>%
    group_by(b) %>%
    do(
        my_function(data=.)
    )

Upvotes: 4

Views: 520

Answers (1)

jenswirf
jenswirf

Reputation: 7307

my_function<-function(data) {
  if(data$a<0) {
    return(data.frame(NULL)) 
  } else {
    return(data.frame(ln=log(data$a)))
  }
}

Upvotes: 2

Related Questions