dotchart2: Enhanced Dot Chart

View source: R/summary.formula.s

dotchart2R Documentation

Enhanced Dot Chart


dotchart2 is an enhanced version of the dotchart function with several new options.


dotchart2(data, labels, groups=NULL, gdata=NA, horizontal=TRUE, pch=16,
          xlab='', ylab='', xlim=NULL, auxdata, auxgdata=NULL, auxtitle,
          lty=1, lines=TRUE, dotsize = .8,
          cex = par("cex"), cex.labels = cex,
 = cex.labels*1.25, sort.=TRUE, 
	      add=FALSE, dotfont=par('font'), groupfont=2, 
	      reset.par=add, xaxis=TRUE, width.factor=1.1,
          lcolor='gray', leavepar=FALSE,
          axisat=NULL, axislabels=NULL, ...)



a numeric vector whose values are shown on the x-axis


a vector of labels for each point, corresponding to x. If omitted, names(data) are used, and if there are no names, integers prefixed by "#" are used.


an optional categorical variable indicating how data values are grouped


data values for groups, typically summaries such as group medians


set to FALSE to make the chart vertical instead of the default


default character number or value for plotting dots in dot charts. The default is 16.


x-axis title


y-axis title


x-axis limits. Applies only to horizontal=TRUE.


a vector of auxiliary data given to dotchart2, of the same length as the first (data) argument. If present, this vector of values will be printed outside the right margin of the dot chart. Usually auxdata represents cell sizes.


similar to auxdata but corresponding to the gdata argument. These usually represent overall sample sizes for each group of lines.


if auxdata is given, auxtitle specifies a column heading for the extra printed data in the chart, e.g., "N"


line type for horizontal lines. Default is 1 for R, 2 for S-Plus


set to FALSE to suppress drawing of reference lines


cex value for drawing dots. Default is 0.8. Note that the original dotchart function used a default of 1.2.


see par


cex parameter that applies only to the line labels for the dot chart cex parameter for major grouping labels for dotchart2. Defaults to cex.

value of cex corresponding to gdata


set to FALSE to keep dotchart2 from sorting the input data, i.e., it will assume that the data are already properly arranged. This is especially useful when you are using gdata and groups and you want to control the order that groups appear on the chart (from top to bottom).


set to TRUE to add to an existing plot


font number of plotting dots. Default is one. Use -1 to use "outline" fonts. For example, pch=183, dotfont=-1 plots an open circle for UNIX on postscript. pch=1 makes an open octagon under Windows.


font number to use in drawing group labels for dotchart2. Default is 2 for boldface.


set to FALSE to cause dotchart2 to not reset the par parameters when finished. This is useful when add=TRUE is about to be used in another call. The default is to reset the par parameters if add=TRUE and not if add=FALSE, i.e., the program assumes that only one set of points will be added to an existing set. If you fail to use reset.par=TRUE for the first of a series of plots, the next call to plot with add=TRUE will result in distorted x-axis scaling.


set to FALSE to suppress drawing x-axis


When the calculated left margin turns out to be faulty, specify a factor by which to multiple the left margin as width.factor to get the appropriate space for labels on horizonal charts.


color for horizontal reference lines. Default is "gray" for R, par("col") for S-Plus.


set to TRUE to leave par() unchanged. This assumes the user has allocated sufficient left and right margins for a horizontal dot chart.


a vector of tick mark locations to pass to axis. Useful if transforming the data axis


a vector of strings specifying axis tick mark labels. Useful if transforming the data axis


arguments passed to plot.default

Side Effects

dotchart will leave par altered if reset.par=FALSE.


Frank Harrell
Department of Biostatistics
Vanderbilt University

See Also



maj <- factor(c(rep('North',13),rep('South',13)))
g <- paste('Category',rep(letters[1:13],2))
n <- sample(1:15000, 26, replace=TRUE)
y1 <- runif(26)
y2 <- pmax(0, y1 - runif(26, 0, .1))
dotchart2(y1, g, groups=maj, auxdata=n, auxtitle='n', xlab='Y')
dotchart2(y2, g, groups=maj, pch=17, add=TRUE)
## Compare with dotchart function (no superpositioning or auxdata allowed):
## dotchart(y1, g, groups=maj, xlab='Y')

## To plot using a transformed scale add for example
## axisat=sqrt(pretty(y)), axislabels=pretty(y)

Hmisc documentation built on April 19, 2022, 9:05 a.m.