[R] how to find unique pairs of variables?
gunter.berton at gene.com
Thu Sep 15 18:39:58 CEST 2011
1. As usual, see FAQ 7.31. unique() may not mean what you think it
means for finite precision numbers:
> unique(c(1/3, sqrt(2)*1/3/sqrt(2)))
 0.3333333 0.3333333
But modulo that: unique(paste(v1,v2))
will give you what you're looking for I think.
On Thu, Sep 15, 2011 at 9:27 AM, <bby2103 at columbia.edu> wrote:
> I have two variables, both numerical. I would like to find the unique values
> of the pairs, in other words, unique coordinates if I were to plot them.
> I also need to know how many pairs there are, but I guess I can use length()
> if I can somehow isolate the unique pairs first?
> Thanks a lot!
> Bonnie Yuan
> R-help at r-project.org mailing list
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.
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Genentech Nonclinical Biostatistics
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