That does the trick with base functions! Thanks Dennis. Ivan -- Ivan Calandra, PhD University of Reims Champagne-Ardenne GEGENAA - EA 3795 CREA - 2 esplanade Roland Garros 51100 Reims, France +33(0)3 26 77 36 89 ivan.calandra at univ-reims.fr -- https://www.researchgate.net/profile/Ivan_Calandra https://publons.com/author/705639/ Le 17/03/2016 20:48, Dennis Murphy a ?crit :> Hi: > > Try > > mydf <- data.frame(let=rep(letters[1:3],each=3), num=rnorm(9), > stringsAsFactors=FALSE) > > stripchart(num ~ let, data = mydf, pch = 19, vertical = TRUE) > > > Dennis > > On Thu, Mar 17, 2016 at 3:29 AM, Ivan Calandra > <ivan.calandra at univ-reims.fr> wrote: >> Dear useRs, >> >> I would like to plot data points in a simple scatterplot. I don't have a lot >> of data per category, so a boxplot does not make sense. >> >> Here are some sample data: >> mydf <- data.frame(let=rep(letters[1:3],each=3), num=rnorm(9), >> stringsAsFactors=FALSE) >> >> I would like to do that, which throws an error, most likely because x is >> character: >> plot(mydf$let, mydf$num) >> >> If I convert to factor(), it plots a boxplot with no possibility (AFAIK) to >> plot points: >> mydf$let <- factor(mydf$let) >> plot(mydf$let, mydf$num, type='p') >> >> I know I can use the function points() in a somewhat convoluted manner: >> plot(mydf$num, xlim=c(1,3), type='n', xaxt='n') >> axis(side=1, at=1:3, labels=levels(mydf$let)) >> points(as.numeric(mydf$let), mydf$num) >> >> Isn't there a simple(r) way? Maybe I just missed something obvious... >> >> Thank you in advance for your help, >> Ivan >> >> -- >> Ivan Calandra, PhD >> University of Reims Champagne-Ardenne >> GEGENAA - EA 3795 >> CREA - 2 esplanade Roland Garros >> 51100 Reims, France >> +33(0)3 26 77 36 89 >> ivan.calandra at univ-reims.fr >> -- >> https://www.researchgate.net/profile/Ivan_Calandra >> https://publons.com/author/705639/ >> >> ______________________________________________ >> R-help at 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.