Test should be

if(is.na(mat$Plant)){ ...



On Tue, 5 Dec 2006, 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
>
> ______________________________________________
> [email protected] 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.
>

_________________________________________________________________
David Scott     Visiting (Until January 07)
                Department of Probability and Statistics
                The University of Sheffield
                The Hicks Building
                Hounsfield Road
                Sheffield S3 7RH
                United Kingdom
Phone:  +44 114 222 3908
Email:  [EMAIL PROTECTED]

______________________________________________
[email protected] 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