Dear Dave, Another option would be to manually create the breaks of your plot.
library(ggplot2) myBreaks <- sort(c(pretty(mtcars$mpg), min(mtcars$mpg))) ggplot(aes(x = wt, y = mpg), data = mtcars) + geom_point() + geom_hline(yintercept = min(mtcars$mpg)) + scale_y_continuous(breaks = myBreaks) HTH, Thierry ---------------------------------------------------------------------------- ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek / Research Institute for Nature and Forest Cel biometrie, methodologie en kwaliteitszorg / Section biometrics, methodology and quality assurance Gaverstraat 4 9500 Geraardsbergen Belgium tel. + 32 54/436 185 [email protected] www.inbo.be To call in the statistician after the experiment is done may be no more than asking him to perform a post-mortem examination: he may be able to say what the experiment died of. ~ Sir Ronald Aylmer Fisher The plural of anecdote is not data. ~ Roger Brinner The combination of some data and an aching desire for an answer does not ensure that a reasonable answer can be extracted from a given body of data. ~ John Tukey -----Oorspronkelijk bericht----- Van: [email protected] [mailto:[email protected]] Namens baptiste auguie Verzonden: dinsdag 3 maart 2009 21:50 Aan: Dave Murray-Rust CC: R Help Onderwerp: Re: [R] ggplot2: annotated horizontal lines I see your problem (although label should be outside the mapping in your case, i think). A possible workaround is to provide some dummy data, as the default NULL doesn't seem to work, qplot( wt, mpg, data=mtcars ) + geom_text(data=data.frame(x=0,y=0),mapping=aes(x=1,y=0),label="test") I'm sure Hadley will come up with a better explanation. Best, baptiste On 3 Mar 2009, at 19:51, Dave Murray-Rust wrote: > > On 3 Mar 2009, at 18:41, baptiste auguie wrote: > >> What's wrong with geom_text? >> >>> my.value = 0.65 >>> qplot(1,1)+geom_hline(v=0)+ >>> geom_text(mapping=aes(x=1,y=0),label=paste(my.value),vjust=-1) >> > > Well, firstly I hadn't thought to use it. Ooops. > > Secondly, I can't make it just do a single value - it seems to want a > value for every point in the dataset, e.g.: > >> qplot( wt, mpg, data=mtcars ) + > geom_text(mapping=aes(x=1,y=0,label=paste("0.5"),vjust=-1)) > Error in data.frame(..., check.names = FALSE) : > arguments imply differing number of rows: 1, 32 > > Cheers, > dave > > >> >> baptiste >> >> On 3 Mar 2009, at 18:10, Dave Murray-Rust wrote: >> >>> Hello, >>> >>> I'm using geom_hline to add a minimum line to my plot (representing >>> the best solution found so far by a search algorithm). I'd like to >>> annotate this line with it's numerical value to save trying to read >>> it >>> off the graph, but I can't see a clear way to do this - any ideas? >>> >>> (Alternatively, if this is against the spirit of the grammar of >>> graphics, is there a better way to represent the information?) >>> >>> Cheers, >>> dave >>> >>> >>> -- >>> The University of Edinburgh is a charitable body, registered in >>> Scotland, with registration number SC005336. >>> >>> ______________________________________________ >>> [email protected] 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. >> >> _____________________________ >> >> Baptiste Auguié >> >> School of Physics >> University of Exeter >> Stocker Road, >> Exeter, Devon, >> EX4 4QL, UK >> >> Phone: +44 1392 264187 >> >> http://newton.ex.ac.uk/research/emag >> ______________________________ >> >> > > > -- > The University of Edinburgh is a charitable body, registered in > Scotland, with registration number SC005336. > _____________________________ Baptiste Auguié School of Physics University of Exeter Stocker Road, Exeter, Devon, EX4 4QL, UK Phone: +44 1392 264187 http://newton.ex.ac.uk/research/emag ______________________________________________ [email protected] 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. Dit bericht en eventuele bijlagen geven enkel de visie van de schrijver weer en binden het INBO onder geen enkel beding, zolang dit bericht niet bevestigd is door een geldig ondertekend document. The views expressed in this message and any annex are purely those of the writer and may not be regarded as stating an official position of INBO, as long as the message is not confirmed by a duly signed document. ______________________________________________ [email protected] 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.
