Hello,

I have a dataframe consisting of two columns.

> col1<-factor(c("a","a","b","b","c","c"))
> col2<-factor(c("a","b","c","d","e","f"))
> somedf<-data.frame(col1,col2)
> somedf
    col1   col2
1      a      d
2      a      e
3      b      f
4      b      g
5      c      h
6      c      i

> sample(col1,2,replace=T)
[1] b c
Levels: a b c

Now I want to sample from col2, but I want to restrict a vector I am going to sample from to only those elements that correspond to col1 That is, I want to take a sample from f, g, h, i. Elements corresponding to level a need to be dropped.

   col1    col2

3      b      f
4      b      g
5      c      h
6      c      i

Any ideas?
Thanks in advance!

______________________________________________
R-help@r-project.org mailing list
https://stat.ethz.ch/mailman/listinfo/r-help
PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.

Reply via email to