Georg Otto <[EMAIL PROTECTED]> writes: > Thanks a lot for your help! > > Now I have a related problem, that I still can not solve: > > I plot a t distribution using: > > curve(dt(x, df = 20), xlim=c(-5,5)) > > The upper 5% of that distribution using: > > qt(0.05, df=20, lower.tail=FALSE) > > How can define the polygon to highlight the area representing the > upper 5% of values?
curve(dt(x, df = 20), xlim=c(-5,5)) x0 <- qt(0.05, df=20, lower.tail=FALSE) xmax <- 5 x <- seq(x0, xmax, length=100) # or whatever it takes polygon(c(x0, x, xmax),c(0, dt(x, df = 20), 0), col="red") > Thanks a lot! > > Georg > > "Ken Knoblauch" <[EMAIL PROTECTED]> writes: > > > How about, > > > > d<-density(rnorm(10000)) > > plot(d) > > wvs <- which(d$x > 1 & d$x < 2) > > polygon(d$x[c( wvs[1], wvs, wvs[length(wvs)] ) ], c(0, d$y[wvs], 0), col = > > "bisque") > > > > Georg Otto a écrit: > > Hi, > > > > if I plot a normal distribution like this: > > > > d<-density(rnorm(10000)) > > plot(d) > > > > how can I highlight the area below the graph in a certain interval, > > say x=1,2? I understand that I should use polygon, but I have not > > found the right way to give the result that I want. > > > > . > > ______________________________________________ > [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 > -- O__ ---- Peter Dalgaard Øster Farimagsgade 5, Entr.B c/ /'_ --- Dept. of Biostatistics PO Box 2099, 1014 Cph. K (*) \(*) -- University of Copenhagen Denmark Ph: (+45) 35327918 ~~~~~~~~~~ - ([EMAIL PROTECTED]) FAX: (+45) 35327907 ______________________________________________ [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
