This class of objects is returned by high level lattice functions, and
is usually plotted by default by its
print method.
A trellis object, as returned by high level lattice functions like
xyplot, is a list with the "class" attribute set
to "trellis". Many of the components of this list are simply
the arguments to the high level function that produced the object.
Among them are: as.table, layout, page,
panel, prepanel, main, sub,
par.strip.text, strip, skip, xlab
ylab, par.settings, lattice.options and
plot.args. Some other typical components are:
formulathe Trellis formula used in the call
index.condlist with index for each of the conditioning variables
perm.condpermutation of the order of the conditioning variables
aspect.filllogical, whether aspect is "fill"
aspect.rationumeric, aspect ratio to be used if aspect.fill is
FALSE
callcall that generated the object.
condlevelslist with levels of the conditioning variables
legendlist describing the legend(s) to be drawn
panel.argsa list as long as the number of panels, each element being a list itself, containing the arguments in named form to be passed to the panel function in that panel.
panel.args.commona list containing the arguments common to all the panel functions
in name=value form
x.scaleslist describing x-scale, can consist of several other lists,
paralleling panel.args, if x-relation is not "same"
y.scaleslist describing y-scale, similar to x.scales
x.betweennumeric vector of interpanel x-space
y.betweennumeric vector of interpanel y-space
x.limitsnumeric vector of length 2 or list, giving x-axis limits
y.limitssimilar to x.limits
packet.sizesarray recording the number of observations in each packet