How to remove objects with rm()

Question

aaa<-function() {
  for (i in 1:2) {
    rm(paste("aaa",i,sep=""),pos = ".GlobalEnv")
  }
}

aaa1<-"e!f!g!h!"
aaa2<-"e!f!g!h!"
aaa()

I tried to remove aaa1 and aaa2 with loop, but it doesn't seem to work.

score 2 · Accepted Answer · answered May 15 '14 at 04:34

2

You cannot pass a function that returns a character vector like that to rm. For example if you run

aaa1<-12   
x<-"aaa1"
rm(x)

it will remove x, not aaa1. So you can't remove variables by giving a list of strings to rm() like that.

However, rm() does have list= parameter that does allow you to specify a character vector. so

aaa<-function() {
  for (i in 1:2) {
    rm(list=paste("aaa",i,sep=""),pos = ".GlobalEnv")
  }
}

aaa1<-"e!f!g!h!"
aaa2<-"e!f!g!h!"
aaa()

will work.

answered May 15 '14 at 04:34

MrFlick

`rm(list=ls(pattern="aaa\\d+$"))` or something similar is probably preferable to looping though. – thelatemail May 15 '14 at 04:41
@thelatemail Good point. I was just focusing on the `rm` part. I can't imagine the real function looks exactly like this, but i guess you never know. – MrFlick May 15 '14 at 04:44
@thelatemail rm(list=ls(pattern="aaa\\d+$")) doesn't seem to work. you may run rm(aaa1) after aaa(). – stata May 15 '14 at 04:50
@stata - it works just fine for me and removes aaa1 and aaa2. – thelatemail May 15 '14 at 04:51

1 Answers1