J?rg
To add a level you could:
x <- factor(c("xyz1", "abc1", "xyz2",
"abc2"))
x1 <- factor(x, levels=c(levels(x), 'fgh'))
summary(x)
abc1 abc2 xyz1 xyz2
1 1 1 1
summary(x1)
abc1 abc2 xyz1 xyz2 fgh
1 1 1 1 0
For the others, I tend to convert to a character, make the changes and convert
back to a factor - but there is probably a better way.
HTH ....
Peter Alspach.
> -----Original Message-----
> From: r-help-bounces at r-project.org
> [mailto:r-help-bounces at r-project.org] On Behalf Of J?rg Gro?
> Sent: Tuesday, 16 December 2008 3:26 p.m.
> To: r-help at r-project.org
> Subject: [R] renaming factor-labels / add factors etc.
>
> Hi,
>
> how can I change a defined factor-variable?
> Like adding levels, renaming existing levels or merge several
> levels of a factor to one level?
>
>
>
> For example; following factor-variable is given:
>
> x <- factor(c("xyz1", "abc1", "xyz2",
"abc2"))
>
>
> How can I add the level fgh?
> And how can I merge "xyz1" and "xyz2" to one level?
> And how can I change the name?
>
>
>
>
> Thanks for any help!
>
> ______________________________________________
> R-help at 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.
>
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