x (and
y where appropriate) variables are plotted with different
graphical parameters for each distinct value of the grouping variable.panel.superpose(x, y = NULL, subscripts, groups,
panel.groups = "panel.xyplot",
col, col.line, col.symbol,
pch, cex, font,
fontface, fontfamily,
lty, lwd, alpha,
type = "p",
...)
panel.superpose.2(x, y = NULL, subscripts, groups,
panel.groups = "panel.xyplot",
col, col.line, col.symbol,
pch, cex, font,
fontface, fontfamily,
lty, lwd, alpha,
type = "p",
...)panel.groups gives different
types of plots, for example panel.xyplot,
panel.dotplot and panel.linejoin (This can
be used to produce interaction plots).