Change type of variable with a for loop

Asked Jan 19 '16 at 17:03

Active Jan 19 '16 at 17:04

Viewed 21 times

I have a data set in R and I want to turn the first three columns into a factor with a for loop. What I did is:

newvar=names(data)[1:3]
for(v in newvar){
    data[,v] = as.factor(data[,v])
  }

this works fine. Can anyone tell me why

for( v in newvar){
 data$v=as.factor(data$v)
}

won´t work?

edited Jan 19 '16 at 17:04

David Arenburg

asked Jan 19 '16 at 17:03

Laurie

Because `$` can't evaluate RHS. Let me use my Google-foo for a sec... – David Arenburg Jan 19 '16 at 17:05
For what it's worth, you could get around this with the `[[` notation. For example `for (v in newvar) data[[v]] <- as.factor(data[[v]])` – tblznbits Jan 19 '16 at 17:08
@brittenb they already got around it AFIK – David Arenburg Jan 19 '16 at 17:11

0 Answers0