This help topic is for R version 0.60. For the current version of R, try https://stat.ethz.ch/R-manual/R-patched/library/base/html/axis.html
axis {base}R Documentation

Add an Axis to a Plot

Usage

axis(which, at, labels=TRUE, ...)

Arguments

which

an integer specifying which side of the plot the axis is to be drawn on.

at

the points at which tick-marks are to be drawn.

labels

this can either be a logical value specifying whether (numerical) annotations are to be made at the tickmarks, or a vector of character strings to be placed at the tickpoints.

...

graphical parameters may also be passed as aruments to this function.

Value

This function is invoked for its side effect, which is to add an axis to an already existing plot. The axis is placed as follows: 1=below, 2=left, 3=above and 4=right.

Examples

plot(1:4, rnorm(4), axes=FALSE)
axis(1, 1:4, LETTERS[1:4])
axis(2)
box() #- to make it look "as usual"

##-- This still fails in older versions of R :
plot(1:7, rnorm(7), type = 's', xaxt='n', col = 'red')
axis(1, 1:7, LETTERS[1:7], col.axis = 'blue')

[Package base version 0.60 ]