foo <- c("blue", "red", "green")
foo=as.factor(foo)
foo=as.numeric(as.character(foo))
foo#the numeric ordering is alphabetic hth, daniel ------------------------- cuncta stricte discussurus ------------------------- -----Ursprüngliche Nachricht----- Von: r-help-boun...@r-project.org [mailto:r-help-boun...@r-project.org] Im Auftrag von Noah Silverman Gesendet: Wednesday, August 12, 2009 2:09 PM Cc: r-help@r-project.org Betreff: Re: [R] nominal to numeric function Hi, Thanks for the tip, Neither method works as my data is truly nominal ------------------------------------- foo <- c("blue", "red", "green") as.numeric(foo) [1] NA NA NA Warning message: NAs introduced by coercion ------------------------------------ Rapid Miner has a function that will automatically create an "index" of the values and create a new variable (or replace the existing). It also has a second function that will break the nominal labels into n variable that are binary: i.e. red(0,1) blue(0,1) green(0,1) Or, I guess I could go back to the source that generates my data and institute a numeric key for the nominal items. That seems like the longest way, but probably the safest to get what I want. -N On 8/12/09 9:10 AM, Phil Spector wrote: > It's generally safer to use > > as.numeric(as.character(variablename)) > > since it eliminates problems associated with factors. > > - Phil Spector > Statistical Computing Facility > Department of Statistics > UC Berkeley > spec...@stat.berkeley.edu > > > On Wed, 12 Aug 2009, Daniel Malter wrote: > >> >> Hi you can use newvariable=as.numeric(variablename). This converts >> your factors into numeric variables, but not always with the desired >> result. So make sure that you check whether "newvariable" gives you >> what you want. >> Otherwise recoding by hand is indicated. >> >> Best, >> Daniel >> >> >> >> Noah Silverman-3 wrote: >>> >>> Hi, >>> >>> I'm training an SVM (C-classification from e1071 library) >>> >>> Some of the variables in my data set are nominal. Is there some >>> easy/automatic way to convert them to numerical representations? >>> >>> Thanks, >>> >>> -N >>> >>> ______________________________________________ >>> R-help@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. >>> >>> >> >> -- >> View this message in context: >> http://www.nabble.com/nominal-to-numeric-function-tp24930466p24939723 >> .html >> >> Sent from the R help mailing list archive at Nabble.com. >> >> ______________________________________________ >> R-help@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. >> > > ______________________________________________ > R-help@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. ______________________________________________ R-help@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. ______________________________________________ R-help@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.
