R help - Jan 2003 - ave across columns

Hi:

How do I find average across three columns such as weight1, weight2, 
weight3 (20 people, each person has three different measures)? They have 
NA's also.  Thanks

Tom, Univ of Pittsburgh, ttrut at yahoo.com

x <- matrix(rnorm(60),20)
x[sample(1:60,10)] <- NA
apply(x,1,mean,na.rm=T)

On Monday, January 20, 2003, at 04:27 PM, Truc Truong wrote:
> Hi:
>
> How do I find average across three columns such as weight1, weight2, 
> weight3 (20 people, each person has three different measures)? They 
> have NA's also.  Thanks
>
> Tom, Univ of Pittsburgh, ttrut at yahoo.com
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> http://www.stat.math.ethz.ch/mailman/listinfo/r-help
>
>
--
http://www.van-rijn.org

On 20 Jan 2003 at 17:46, Hedderik van Rijn wrote:
> x <- matrix(rnorm(60),20)
> x[sample(1:60,10)] <- NA
> apply(x,1,mean,na.rm=T)
or simply

colMeans(x,na.rm=T)
> 
> On Monday, January 20, 2003, at 04:27 PM, Truc Truong wrote:
> 
> > Hi:
> >
> > How do I find average across three columns such as weight1, weight2,
> > weight3 (20 people, each person has three different measures)? They
> > have NA's also.  Thanks
> >
> > Tom, Univ of Pittsburgh, ttrut at yahoo.com
> >
> > ______________________________________________
> > R-help at stat.math.ethz.ch mailing list
> > http://www.stat.math.ethz.ch/mailman/listinfo/r-help
> >
> >
> --
> http://www.van-rijn.org
> 
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> http://www.stat.math.ethz.ch/mailman/listinfo/r-help
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