Petr, Thanks again, but the data is GQ1, Max is a variable (column)
So I have used by(GQ1[,"Max"], list(GQ1$Status), summary) Which is very good, and is better than the way I did it before by summarising for each status level individually, but that still isn't combing the data for Status == "Expert" and Status = "Ecol" So at the moment the status variable has 3 levels Expert, Ecol and Stake, I want to analsye that at two levels: Expert and Ecol combined into a new level called "AllEcol" and the exsiting level "Stake" It is this combining the levels that has got me stuck. Thanks again, Graham On 08/09/06, Petr Pikal <[EMAIL PROTECTED]> wrote: > > Sorry, I did not notice that in your case Max is not a function but > your data. So probably > > by(Max[, your.columns], list(Max$status), summary) > > is maybe what you want. > HTH > Petr > > > On 8 Sep 2006 at 10:31, Petr Pikal wrote: > > From: "Petr Pikal" <[EMAIL PROTECTED]> > To: "Graham Smith" <[EMAIL PROTECTED]>, > 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" <[EMAIL PROTECTED]> > > 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 > > [EMAIL PROTECTED] > > > > ______________________________________________ > > 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 > [EMAIL PROTECTED] > > [[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.
