[R] excluding factor levels with read.table() and colClasses=

[Dieter Menne]

Peter Tait <petertait <at> sympatico.ca> writes:

> Is it possible to remove the "NA" level from a factor with in 
> read.table()?  If not  what is the most efficient  way of doing this?
> 
> inrange<-read.table("C://...",header=T,sep="|",colClasses=c( id="factor"))

See parameters na.strings in read.table. 

Dieter