Extend xyplot
to superpose one or more symbols to each panel.
xyplot2(formula, data, type = "l", ...)
On each panel, several plot types, the length of data
, are superposed.
a two-sided formula as accepted in xyplot
a list of data frames. Each component shall be able to evaluate the vatiables appearing in formula
a vector of characters to indicate what type of plots are to draw. Default is line.
any options as accepted in xyplot