dataViewport(xData = NULL, yData = NULL, xscale = NULL,
yscale = NULL, extension = 0.05, ...)
viewport()
function. xscale
is not specified then the values in x
are
used to generate an x-scale based on the range of x
, extended
by the proportion specified in extension
. Similarly for the
y-scale.viewport
and
plotViewport
.