add.scale.bar: Add a Scale Bar to a Phylogeny Plot
Description
This function adds a horizontal bar giving the scale of the branch
lengths to a plot of a phylogenetic tree on the current graphical
device.
Usage
add.scale.bar(x = 0, y = 1, length = NULL, ...)
Arguments
x
x location of the bar.
y
y location of the bar.
length
a numeric value giving the length of the scale bar. If
none is supplied, a value is calculated from the data.
...
further arguments to be passed to text.
Details
As from version 1.4 of ape, the options of this function have been
redefined, and have now default values. By default, the scale bar is
plotted on the left bottom corner of the plot.
The further arguments (...) are used to format the text. They
may be font, cex, col, and so on (see examples
below, and the help page on text).
The function locator may be used to
determine the x and y arguments.