Hi
a little bit quicker solution is based on subsetting and a fact that
logical vector can be treated as numeric with FALSE=0 and TRUE = 1
Plant<-sample(c(NA,1), 100000, replace=T);
Value1<-rnorm(Plant);
Value2<-rnorm(Plant);
mat<-data.frame(Plant=Plant,Value1=Value1,Value2=Value2)
> system.time(mat$Plant1<-c("B","A")[is.na(mat$Plant)+1])
[1] 0.03 0.02 0.05 NA NA
> system.time(mat$Plant2 <- ifelse(is.na(mat$Plant), "A", "B"))
[1] 0.28 0.01 0.30 NA NA
> with(mat, all.equal(Plant1, Plant2))
[1] TRUE
HTH
Petr
On 6 Dec 2006 at 6:39, Andrew Robinson wrote:
Date sent: Wed, 6 Dec 2006 06:39:32 +1100
From: Andrew Robinson <[EMAIL PROTECTED]>
To: Hans-Juergen Eickelmann <[EMAIL PROTECTED]>
Copies to: r-help@stat.math.ethz.ch
Subject: Re: [R] if(){} else{}
> Hi Hans,
>
> try this ...
>
> mat <- as.data.frame(cbind(Plant,Value1,Value2))
>
> mat$Plant1 <- ifelse(is.na(mat$Plant), "A", "B")
>
> Cheers
>
> Andrew
>
>
> On Tue, Dec 05, 2006 at 04:33:15PM +0100, Hans-Juergen Eickelmann
> wrote: > > Dear R-community, > > my data set looks like 'mat' below. >
> > Plant<-c(NA,1,1,1,NA,NA,NA,NA,NA,1); > Value1<-rnorm(1:10); >
> Value2<-rnorm(1:10); > mat<-cbind(Plant,Value1,Value2); > I receive
> data from two different sites. > One site is identified by an interger
> number, the other site has no data in > column Plant=NA. > > My pb: >
> > I'm trying to assign labels "A" or "B" to these 2 sites into a new
> column, > but my if(){} else{} statement fails with the following
> statement: > Error in if (is.na(mat$Plant == TRUE)) { : >
> argument is of length zero > >
> if(is.na(mat$Plant==TRUE)){mat$Plant1="A"} else{mat$Plant1="B"}; > > I
> looked through the avail doc and R-help for some time but wasn't able
> to > fix the pb. > > Thx Hans > >
> ______________________________________________ >
> R-help@stat.math.ethz.ch 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.
>
> --
> Andrew Robinson
> Department of Mathematics and Statistics Tel:
> +61-3-8344-9763 University of Melbourne, VIC 3010 Australia
> Fax: +61-3-8344-4599 http://www.ms.unimelb.edu.au/~andrewpr
> http://blogs.mbs.edu/fishing-in-the-bay/
>
> ______________________________________________
> R-help@stat.math.ethz.ch 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.
Petr Pikal
[EMAIL PROTECTED]
______________________________________________
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PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
and provide commented, minimal, self-contained, reproducible code.
