strip.default: In-built Trellis Strip Function

Description

strip.default is the function that draws the strips by default in conditioning Trellis plots. Users can write their own strip functions, but most commonly this involves calling strip.default with a slightly different arguments. strip.custom provides a convenient way to obtain new strip functions that differ from strip.default only in the default values of certain arguments.

Usage

strip.default(which.given,
              which.panel,
              var.name,
              factor.levels,
              shingle.intervals,
              strip.names = c(FALSE, TRUE),
              style = 1,
              bg = trellis.par.get("strip.background")$col[which.given],
              fg = trellis.par.get("strip.shingle")$col[which.given],
              par.strip.text = trellis.par.get("add.text"))
strip.custom(...)

Arguments

which.given

integer index specifying which of the conditioning variables this strip corresponds to.

which.panel

vector of integers as long as the number of conditioning variables. The contents are indices specifing the current levels of each of the conditioning variables (thus, this would be unique for each distinct panel).

var.name

vector of character strings or ecpressions as long as the number of conditioning variables. The contents are the names of the conditioning variables, to be used if the appropriate entry in strip.names (see below) is true.

factor.levels

if the current strip corresponds to a factor, this should be a character or expression vector giving the levels of the factor. Otherwise, it should be NULL

shingle.intervals

if the current strip corresponds to a shingle, this should be a 2-column matrix giving the levels of the shingle. (of the form that would be produced by printing levels(shingle)). Otherwise, it should be NULL

strip.names

a logical vector of length 2, indicating whether or not the name of the conditioning variable that corresponds to the strip being drawn is to be written on the strip. The two components give the values for factors and shingles respectively.

style

integer, with values 1,2,3,4,5 and 6 currently supported. Applicable only when x is a factor. Determines how the current level of x is indicated on the strip.

The best way to find out what effect the value of s

par.strip.text

list with parameters controlling the text on each strip, with components col, cex, font

strip background color.

strip foreground color.

...

arguments to be passed on to strip.default, overriding whatever value it would have normally assumed

Value

strip.default is useful for its side-effect, which is to draw a strip appropriate for conditioning Trellis plots. strip.default returns a function similar to strip.default

Details

default strip function for trellis functions. Useful mostly because of the style argument --- non-default styles are often more informative, especially when the names of the levels of the factor x are small. Typical use is as strip = function(...) strip.default(style=2,...).

Examples

Run this code

xyplot(Petal.Length ~ Petal.Width | Species, iris,
       strip = strip.custom(style = 4))