Let me see if I can ask the question more clearly - I am trying to extract a section of a hyphenated factor. For example, 001-004 is one observation of test$ken, which is a factor, and I want to set up a new factor variable called place that would have 001 as an observation. If I call mutate(place = (as.character (test$ken)), I can extract 001 from 001-004, but but don't know how to subsequently convert that character string back into a factor.
Or can 001 be extracted from a factor as a factor? Do you know how to execute either of these approaches? Ken kmna...@gmail.com 914-450-0816 (tel) 347-730-4813 (fax) > On Mar 3, 2016, at 8:33 PM, Hervé Pagès <hpa...@fredhutch.org> wrote: > > On 03/03/2016 02:13 PM, KMNanus wrote: >> When I do that, > > When you do what exactly? > > It's impossible for anyone here to know what you're doing if you > don't show the code. > >> I get "Error in `$<-.data.frame`(`*tmp*`, "site", value >> = integer(0)) : >> replacement has 0 rows, data has 6” >> >> The data frame has 6 rows. > > You said you had a factor variable, you never mentioned you had a > data.frame. If the factor variable is part of a data.frame 'df', > then first extract it with something like df$myvar or df[["myvar"]], > and then call substr() followed by as.factor() on it. > > H. > >> >> Ken >> kmna...@gmail.com <mailto:kmna...@gmail.com> >> 914-450-0816 (tel) >> 347-730-4813 (fax) >> >> >>> On Mar 3, 2016, at 4:52 PM, Hervé Pagès <hpa...@fredhutch.org >>> <mailto:hpa...@fredhutch.org>> wrote: >>> >>> Hi, >>> >>> On 03/03/2016 12:18 PM, KMNanus wrote: >>>> I have a factor variable that is 6 digits and hyphenated. For >>>> example, 001-014. >>>> >>>> I need to extract the first 3 digits to a new variable using mutate >>>> in dplyr - in this case 001 - but can’t find a function to do it. >>>> >>>> substr will do this for character strings, but I need the variable to >>>> remain as a factor. >>> >>> What prevents you from calling as.factor() on the result to turn it >>> back into a factor? >>> >>> H. >>> >>>> >>>> Is there an R function or workaround to do this? >>>> >>>> >>>> Ken >>>> kmna...@gmail.com <mailto:kmna...@gmail.com> >>>> 914-450-0816 (tel) >>>> 347-730-4813 (fax) >>>> >>>> >>>> >>>> ______________________________________________ >>>> R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see >>>> 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. >>>> >>> >>> -- >>> Hervé Pagès >>> >>> Program in Computational Biology >>> Division of Public Health Sciences >>> Fred Hutchinson Cancer Research Center >>> 1100 Fairview Ave. N, M1-B514 >>> P.O. Box 19024 >>> Seattle, WA 98109-1024 >>> >>> E-mail: hpa...@fredhutch.org <mailto:hpa...@fredhutch.org> >>> Phone: (206) 667-5791 >>> Fax: (206) 667-1319 >> > > -- > Hervé Pagès > > Program in Computational Biology > Division of Public Health Sciences > Fred Hutchinson Cancer Research Center > 1100 Fairview Ave. N, M1-B514 > P.O. Box 19024 > Seattle, WA 98109-1024 > > E-mail: hpa...@fredhutch.org > Phone: (206) 667-5791 > Fax: (206) 667-1319 ______________________________________________ R-help@r-project.org mailing list -- To UNSUBSCRIBE and more, see 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.
