character string telling how to plot the
x and
y values:
"p" for points,
"l" for lines, and
"b" for both.
...
graphical parameters that are passed to
points or
lines.
By default,
the trellis parameter list
plot.symbol will be used to control
character size (
cex ), plotting symbol (
pch ), font (
font ),
and color (
col ) for points;
the
plot.line parameters will be used to control
line width (
lwd ), line type (
lty ), and color (
col ) for lines.
SIDE EFFECTS:
The points or lines are plotted along with a horizontal
reference line through the origin (
y = 0 ).