R help - Jul 2011 - elegant way of removing NA's and selecting specific values from a data.frame

I have a data.frame "e" and would like to extract the 23rd column, 
remove any NA's and then remove any values >= 30.  I can do it in steps 
such as this but have failed to figure out how to do it in a single line 
.... any suggestions?

first <- e[,23]
second <- first[!is.na(first)]
third <- second[second<=30]

thanks a bunch

J

-- 
Dr. Jim Maas
University of East Anglia

?"&"

This is basic. Please read "An Intro to R" before posting any more
such questions if you have not already done so.

-- Bert

On Wed, Jul 6, 2011 at 8:35 AM, Jim Maas <j.maas at uea.ac.uk>
wrote:
> I have a data.frame "e" and would like to extract the 23rd
column, remove
> any NA's and then remove any values >= 30. ?I can do it in steps
such as
> this but have failed to figure out how to do it in a single line .... any
> suggestions?
>
> first <- e[,23]
> second <- first[!is.na(first)]
> third <- second[second<=30]
>
> thanks a bunch
>
> J
>
> --
> Dr. Jim Maas
> University of East Anglia
>
> ______________________________________________
> 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.
>


-- 
"Men by nature long to get on to the ultimate truths, and will often
be impatient with elementary studies or fight shy of them. If it were
possible to reach the ultimate truths without the elementary studies
usually prefixed to them, these would not be preparatory studies but
superfluous diversions."

-- Maimonides (1135-1204)

Bert Gunter
Genentech Nonclinical Biostatistics