Dear Beto, The code below gives a correct result.
library(ggplot2) df <- data.frame( trt = factor(c("intact", "intact", "removed", "removed")), coon = c(0.093, 0.06, 0.057, 0.09), group = factor(c("veget", "fruit", "veget", "fruit")), se = c(0.01, 0.01, 0.02, 0.026)) ggplot(df, aes(x=trt, y=coon, fill = group, ymax = coon + se, ymin = coon - se)) + geom_bar(position = "dodge", stat="identity") + geom_errorbar(position = "dodge") ------------------------------------------------------------------------ ---- ir. Thierry Onkelinx Instituut voor natuur- en bosonderzoek team Biometrie & Kwaliteitszorg Gaverstraat 4 9500 Geraardsbergen Belgium Research Institute for Nature and Forest team Biometrics & Quality Assurance Gaverstraat 4 9500 Geraardsbergen Belgium tel. + 32 54/436 185 thierry.onkel...@inbo.be 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: r-help-boun...@r-project.org > [mailto:r-help-boun...@r-project.org] Namens hpdutra > Verzonden: vrijdag 12 maart 2010 2:16 > Aan: r-help@r-project.org > Onderwerp: [R] simple plot in ggplot2, wrong error bars > > > I was wondering if anyone could help me with this, simple problem. > > I am essentially following the example on Hadley's webpage > (http://had.co.nz/ggplot2/geom_errorbar.html), but it still > doesn't make any > sense to me. > > > df <- data.frame(trt = factor(c("intact", "intact", > "removed", "removed")), > coon = c(0.093, 0.06, 0.057, 0.09), group = factor(c("veget", "fruit", > "veget", "fruit")), se = c(0.01, 0.01, 0.02, 0.026)) > limits <- aes(ymax = coon + se, ymin=coon - se) > p<-ggplot(df, aes(fill=group, y=coon, x=trt)) > p+geom_bar(position="dodge",stat="identity") > dodge <- position_dodge(width=0.9) > > p + geom_bar(position="dodge") + geom_errorbar(limits, > position="dodge", > > width=0.5) > > as you noticed the code above gets the error bars in the > wrong columns. > So I used the code below (I replaced position_dodge w/ a > negative value and > geom_errorbarr with dodge no quote marks) > > df <- data.frame(trt = factor(c("intact", "intact", > "removed", "removed")), > coon = c(0.093, 0.06, 0.057, 0.09), group = factor(c("veget", "fruit", > "veget", "fruit")), se = c(0.01, 0.01, 0.02, 0.026)) > limits <- aes(ymax = coon + se, ymin=coon - se) > p<-ggplot(df, aes(fill=group, y=coon, x=trt)) > p+geom_bar(position="dodge",stat="identity") > dodge <- position_dodge(width=-0.9) > > p + geom_bar(position="dodge") + geom_errorbar(limits, > position=dodge, > > width=0.5) > > > Why do I need to use negative values to get the right > errorbar structure, > why do I need use doge without quote marks? > Thanks > > Beto > > > > -- > View this message in context: > http://n4.nabble.com/simple-plot-in-ggplot2-wrong-error-bars-t > p1589994p1589994.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. > Druk dit bericht a.u.b. niet onnodig af. Please do not print this message unnecessarily. 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. ______________________________________________ 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.