Control over lattice plots are provided through a collection of user
specifiable functions that perform various tasks during the plotting.
Not all information is available to all functions. The functions
documented here attempt to provide a consistent interface to access
relevant information from within these user specified functions,
namely those specified as the panel, strip and
axis functions. Note that this information is not available to
the prepanel function, which is executed prior to the actual
plotting.
current.row(prefix)
current.column(prefix)
panel.number(prefix)
packet.number(prefix)
which.packet(prefix)trellis.currentLayout(which = c("packet", "panel"), prefix)
whether return value (a matrix) should contain panel numbers or packet numbers, which are usually, but not necessarily, the same (see below for details).
A character string acting as a prefix identifying the plot of a
"trellis" object. Only relevant when a particular page is
occupied by more than one plot. Defaults to the value appropriate
for the last "trellis" object printed. See
trellis.focus.
trellis.currentLayout returns a matrix with as many rows and
columns as in the layout of panels in the current plot. Entries in
the matrix are integer indices indicating which packet (or panel; see
below) occupies that position, with 0 indicating the absence of a
panel. current.row and current.column return integer
indices specifying which row and column in the layout are currently
active. panel.number returns an integer counting which panel
is being drawn (starting from 1 for the first panel, a.k.a. the panel
order). packet.number gives the packet number according to the
packet order, which is determined by varying the first conditioning
variable the fastest, then the second, and so on. which.packet
returns the combination of levels of the conditioning variables in the
form of a numeric vector as long as the number of conditioning
variables, with each element an integer indexing the levels of the
corresponding variable.