R help - Feb 2005 - skip missing values in plots

I really like these Trellis graphics but how do I get this code to 
skip the missing?

logreg<-read.csv("logreg.csv", header=TRUE, sep=",",
na.string=" ")
attach(logreg)

bwplot(yesno~bc_pcb_tot |varlist, data=logreg, main="Box Cox PCB 
transformation",  auto.key=TRUE, fontfamily = "HersheySans" )


Dean Sonneborn M.S.
Public Health Sciences *
University of California, Davis
916 734-6656

* formerly Epidemiology & Preventive Medicine

	[[alternative HTML version deleted]]

Dean Sonneborn wrote:
>          I really like these Trellis graphics but how do I get this code to
> skip the missing?

What is missing here? Some precision in your question, perhaps?
We do not have logreg.csv, so please tell us what is going on, or even 
better specify a minimal reproducible example, as the posting guide 
suggests.

> logreg<-read.csv("logreg.csv", header=TRUE, sep=",",
na.string=" ")
> attach(logreg)
Why do you attach()?

Uwe Ligges

> bwplot(yesno~bc_pcb_tot |varlist, data=logreg, main="Box Cox PCB 
> transformation",  auto.key=TRUE, fontfamily = "HersheySans"
)
> 
> 
> Dean Sonneborn M.S.
> Public Health Sciences *
> University of California, Davis
> 916 734-6656
> 
> * formerly Epidemiology & Preventive Medicine
> 
> 	[[alternative HTML version deleted]]
> 
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