These functions create and draw an x-axis.
grid.xaxis(at = NULL, label = TRUE, main = TRUE,
edits = NULL, name = NULL,
gp = gpar(), draw = TRUE, vp = NULL)xaxisGrob(at = NULL, label = TRUE, main = TRUE,
edits = NULL, name = NULL,
gp = gpar(), vp = NULL)
A numeric vector of x-value locations for the tick marks.
A logical value indicating whether to draw the labels
on the tick marks, or an expression or character vector which
specify the labels to use. If not logical, must be the same
length as the at argument.
A logical value indicating whether to draw the axis
at the bottom (TRUE) or at the top (FALSE) of the
viewport.
A gEdit or gEditList containing edit operations
to apply (to the children of the axis)
when the axis is first created and during redrawing
whenever at is NULL.
A character identifier.
An object of class gpar, typically the output
from a call to the function gpar. This is basically
a list of graphical parameter settings.
A logical value indicating whether graphics output should be produced.
A Grid viewport object (or NULL).
An xaxis grob. grid.xaxis returns the value invisibly.
If the at slot of an xaxis grob is not NULL then
the xaxis will have the following children:
representing the line at the base of the tick marks.
representing the tick marks.
representing the tick labels.
If the at slot is NULL then there are no children
and ticks are drawn based on the current viewport scale.
Both functions create an xaxis grob (a graphical object describing an
xaxis), but only grid.xaxis
draws the xaxis (and then only if draw is TRUE).