1) The boxplot in R does the 25%, 50% and 75% mark as you want 2) Check out the range argument in boxplot. I think you can redefine your 5% and 95% quantile in terms of IQR for symmetric distribution and hence use this feature.
However I find it easier to calculate these numbers manually and feed it into bxp() function. Here is one such function (with lots of room for improvement). matlab.boxplot <- function(m){ m <- as.matrix(m) bp <- boxplot(data.frame(m), plot=FALSE) bp$stats <- apply( m, 2, function(x) quantile(x, c(0.05,0.25, 0.5, 0.75, 0.95), na.rm=T) ) tmp <- apply( m, 2, function(x){ under <- x[ which( x < quantile(x, 0.05, na.rm=T) ) ] over <- x[ which( x > quantile(x, 0.95, na.rm=T) ) ] return( c(under, over) ) }) # always a matrix in this case bp$out <- c(tmp) bp$group <- rep(1:ncol(tmp), each=nrow(tmp)) bxp(bp) } Some usage examples : matlab.boxplot( rnorm(50) ) # a vector my.mat <- matrix( rnorm(300), nc=3 ) matlab.boxplot( my.mat ) # a matrix Regards, Adai On Sun, 2005-07-10 at 18:10 -0500, Larry Xie wrote: > I am trying to draw a plot like Matlab does: > > The upper extreme whisker represents 95% of the data; > The upper hinge represents 75% of the data; > The median represents 50% of the data; > The lower hinge represents 25% of the data; > The lower extreme whisker represents 5% of the data. > > It looks like: > > --- 95% > | > | > ------- 75% > | | > |-----| 50% > | | > | | > ------- 25% > | > --- 5% > > Anyone can give me some hints as to how to draw a boxplot like that? > What function does it? I tried boxplot() but couldn't figure it out. > If it's boxplot(), what arguments should I pass to the function? Thank > you for your help. I'd appreciate it. > > Larry > > ______________________________________________ > R-help@stat.math.ethz.ch mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html > ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html