Re: [R] subsetting a data set

From: Graham Smith <myotisone_at_gmail.com>
Date: Fri 08 Sep 2006 - 09:33:49 GMT

Petr,

Thanks again, but the data is GQ1, Max is a variable (column)

So I have used

 by(GQ1[,"Max"], list(GQ1$Status), summary)

Which is very good, and is better than the way I did it before by summarising for each status level individually, but that still isn't combing the data for Status == "Expert" and Status = "Ecol"

So at the moment the status variable has 3 levels Expert, Ecol and Stake,

I want to analsye that at two levels: Expert and Ecol combined into a new level called "AllEcol" and the exsiting level "Stake"

It is this combining the levels that has got me stuck.

Thanks again,

Graham

On 08/09/06, Petr Pikal <petr.pikal@precheza.cz> wrote:
>
> Sorry, I did not notice that in your case Max is not a function but
> your data. So probably
>
> by(Max[, your.columns], list(Max$status), summary)
>
> is maybe what you want.
> HTH
> Petr
>
>
> On 8 Sep 2006 at 10:31, Petr Pikal wrote:
>
> From: "Petr Pikal" <petr.pikal@precheza.cz>
> To: "Graham Smith" <myotisone@gmail.com>,
> r-help@stat.math.ethz.ch
> Date sent: Fri, 08 Sep 2006 10:31:12 +0200
> Priority: normal
> Subject: Re: [R] subsetting a data set
>
> > Hi
> >
> > I am not sure if your Max is the same as max so I am not sure what you
> > exactly want from your data. However you shall consult ?tapply, ?by,
> > ?aggregate and maybe also ?"[" together with chapter 2 in intro manual
> > in docs directory.
> >
> > aggregate(data[, some.columns], list(data$factor1, data$factor2), max)
> >
> > will give you maximum for specified columns based on spliting the data
> > according to both factors
> >
> > Also connection summary with max is not common and I wonder what is
> > your output in this case. I believe that there are six same numbers.
> > However R is case sensitive and maybe Max does something different
> > from max. In my case it throws an error.
> >
> > HTH
> > Petr
> >
> > On 8 Sep 2006 at 8:06, Graham Smith wrote:
> >
> > Date sent: Fri, 8 Sep 2006 08:06:16 +0100
> > From: "Graham Smith" <myotisone@gmail.com>
> > To: r-help@stat.math.ethz.ch
> > Subject: [R] subsetting a data set
> >
> > > I have a data set called GQ1, which has 20 variables one of which is
> > > a factor called Status at thre levels "Expert", "Ecol" and "Stake"
> > >
> > > I have managed to evaluate some of the data split by status using
> > > commands like:
> > >
> > > summary (Max[Status=="Ecol"])
> > >
> > > BUT how do I produce asummary for Ecol and Expert combined, the
> > > only example I can find suggsts I could use
> > >
> > > summary (Max[Status=="Ecol"& Status=="Expert"]) but that doesn't
> > > work.
> > >
> > > Additionally on the same vein, if I cannot work out how to create a
> > > new data set that would contain all the data for all the variables
> > > but only for the data where Status = Ecol, or where status equalles
> > > Ecol and Expert.
> > >
> > > I know this is yet again a very simple problem, but I really can't
> > > find the solution in the help or the books I have.
> > >
> > > Many thanks,
> > >
> > > Graham
> > >
> > > [[alternative HTML version deleted]]
> > >
> > > ______________________________________________
> > > R-help@stat.math.ethz.ch 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.
> >
> > Petr Pikal
> > petr.pikal@precheza.cz
> >
> > ______________________________________________
> > R-help@stat.math.ethz.ch 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.
>
> Petr Pikal
> petr.pikal@precheza.cz
>
>

        [[alternative HTML version deleted]]



R-help@stat.math.ethz.ch 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. Received on Fri Sep 08 20:50:12 2006

Archive maintained by Robert King, hosted by the discipline of statistics at the University of Newcastle, Australia.
Archive generated by hypermail 2.1.8, at Fri 08 Sep 2006 - 11:30:04 GMT.

Mailing list information is available at https://stat.ethz.ch/mailman/listinfo/r-help. Please read the posting guide before posting to the list.