strip.default            package:lattice            R Documentation

Default Trellis strip function

Description:

     function that draws the strips in conditional trellis plots.

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"))

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.

          This argument is ignored for a factor when 'style' is not one
          of 1 and 3. 

   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 'style' has
          is to try them out. Here is a short description: for a style
          value of 1, the strip is colored in the background color with
          the strip text (as determined by other arguments) centred on
          it. A value of 3 is the same, except that a part of the strip
          is colored in the foreground color, indicating the current
          level of the factor. For styles 2 and 4, the part
          corresponding to the current level remains colored in the
          foreground color, however, for style = 2, the remaining part
          is not colored at all, whereas for 4, it is colored with the
          background color. For both these, the names of all the levels
          of the factor are placed on the strip from left to right.
          Styles 5 and 6 produce the same effect (they are subtly
          different in S, this implementation corresponds to 5), they
          are similar to style 1, except that the strip text is not
          centred, it is instead postioned according to the current
          level.

          Note that unlike S-PLUS, the default value of 'style' is 1. 

par.strip.text: list with parameters controlling the text on each
          strip, with components 'col, cex, font' 

      bg: strip background color. 

      fg: strip foreground color. 

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,...)'.

Author(s):

     Deepayan Sarkar deepayan@stat.wisc.edu

See Also:

     'xyplot', 'Lattice'

