[R] transforming factor back to numbers
Hi I generate a new dataframe by doing: npl.agg - aggregate(npl$DensPlants, list(year=npl$year, sim=npl$sim), mean, na.rm=TRUE ) Now I want to plot it by using coplot(npl.agg$x ~ npl.agg$year | npl.agg$sim, type=l) but, as npl.agg$year is seen as a factor, the order of the points on the x-axis (time axis) does not follow the numerical sorting 1...100, but rather the text sorting of the factor npl.agg$year Is there any way that I can 'defactor' npl.agg$year so that I have again the numerical values for year? Thanks Rainer -- Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation Biology (UCT) Department of Conservation Ecology and Entomology University of Stellenbosch Matieland 7602 South Africa Tel:+27 - (0)72 808 2975 (w) Fax:+27 - (0)21 808 3304 Cell: +27 - (0)83 9479 042 email: [EMAIL PROTECTED] [EMAIL PROTECTED] __ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
Re: [R] transforming factor back to numbers
That's an FAQ: 7.10 How do I convert factors to numeric? It may happen that when reading numeric data into R (usually, when reading in a file), they come in as factors. If f is such a factor object, you can use as.numeric(as.character(f)) to get the numbers back. More efficient, but harder to remember, is as.numeric(levels(f))[as.integer(f)] In any case, do not call as.numeric() or their likes directly for the task at hand (as as.numeric() or unclass() give the internal codes). On 21/09/06, Rainer M Krug [EMAIL PROTECTED] wrote: Hi I generate a new dataframe by doing: npl.agg - aggregate(npl$DensPlants, list(year=npl$year, sim=npl$sim), mean, na.rm=TRUE ) Now I want to plot it by using coplot(npl.agg$x ~ npl.agg$year | npl.agg$sim, type=l) but, as npl.agg$year is seen as a factor, the order of the points on the x-axis (time axis) does not follow the numerical sorting 1...100, but rather the text sorting of the factor npl.agg$year Is there any way that I can 'defactor' npl.agg$year so that I have again the numerical values for year? Thanks Rainer -- Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation Biology (UCT) Department of Conservation Ecology and Entomology University of Stellenbosch Matieland 7602 South Africa Tel:+27 - (0)72 808 2975 (w) Fax:+27 - (0)21 808 3304 Cell: +27 - (0)83 9479 042 email: [EMAIL PROTECTED] [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. -- = David Barron Said Business School University of Oxford Park End Street Oxford OX1 1HP __ 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.
Re: [R] transforming factor back to numbers
Thanks a lot David. Just a suggestion - it might help if this is added to the help of factor() Rainer David Barron wrote: That's an FAQ: 7.10 How do I convert factors to numeric? It may happen that when reading numeric data into R (usually, when reading in a file), they come in as factors. If f is such a factor object, you can use as.numeric(as.character(f)) to get the numbers back. More efficient, but harder to remember, is as.numeric(levels(f))[as.integer(f)] In any case, do not call as.numeric() or their likes directly for the task at hand (as as.numeric() or unclass() give the internal codes). On 21/09/06, Rainer M Krug [EMAIL PROTECTED] wrote: Hi I generate a new dataframe by doing: npl.agg - aggregate(npl$DensPlants, list(year=npl$year, sim=npl$sim), mean, na.rm=TRUE ) Now I want to plot it by using coplot(npl.agg$x ~ npl.agg$year | npl.agg$sim, type=l) but, as npl.agg$year is seen as a factor, the order of the points on the x-axis (time axis) does not follow the numerical sorting 1...100, but rather the text sorting of the factor npl.agg$year Is there any way that I can 'defactor' npl.agg$year so that I have again the numerical values for year? Thanks Rainer -- Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation Biology (UCT) Department of Conservation Ecology and Entomology University of Stellenbosch Matieland 7602 South Africa Tel:+27 - (0)72 808 2975 (w) Fax:+27 - (0)21 808 3304 Cell: +27 - (0)83 9479 042 email: [EMAIL PROTECTED] [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. -- Rainer M. Krug, Dipl. Phys. (Germany), MSc Conservation Biology (UCT) Department of Conservation Ecology and Entomology University of Stellenbosch Matieland 7602 South Africa Tel:+27 - (0)72 808 2975 (w) Fax:+27 - (0)21 808 3304 Cell: +27 - (0)83 9479 042 email: [EMAIL PROTECTED] [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.
