panel.barchart            package:lattice            R Documentation

Default Panel Function for barchart

Description:

     Default panel function for 'barchart'.

Usage:

     panel.barchart(x, y, box.ratio = 1, box.width,
                    horizontal = TRUE,
                    origin = NULL, reference = TRUE,
                    stack = FALSE,
                    groups = NULL, 
                    col = if (is.null(groups)) plot.polygon$col
                          else superpose.polygon$col,
                    border = if (is.null(groups)) plot.polygon$border
                             else superpose.polygon$border,
                    lty = if (is.null(groups)) plot.polygon$lty
                          else superpose.polygon$lty, 
                    lwd = if (is.null(groups)) plot.polygon$lwd
                          else superpose.polygon$lwd,
                    ...)

Arguments:

       x: Extent of Bars. By default, bars start at left of panel,
          unless 'origin' is specified, in which case they start there 

       y: Horizontal location of bars, possibly factor

box.ratio: ratio of bar width to inter-bar space

box.width: thickness of bars in absolute units; overrides 'box.ratio'. 
          Useful for specifying thickness when the categorical variable
          is not a factor, as use of 'box.ratio' alone cannot achieve a
          thickness greater than 1. 

horizontal: logical. If FALSE, the plot is 'transposed' in the sense
          that the behaviours of x and y are switched. x is now the
          'factor'.  Interpretation of other arguments change
          accordingly. See documentation of 'bwplot' for a fuller
          explanation. 

  origin: the origin for the bars.  For grouped displays with 'stack =
          TRUE', this argument is ignored and the origin set to 0. 
          Otherwise, defaults to 'NULL', in which case bars start at
          the left (or bottom) end of a panel.  This choice is somewhat
          unfortuntate, as it can be misleading, but is the default for
          historical reasons.  For tabular (or similar) data, 'origin =
          0' is usually more appropriate; if not, one should reconsider
          the use of a bar chart in the first place (dot plots are
          often a good alternative). 

reference: logical, whether a reference line is to be drawn at the
          origin 

   stack: logical, relevant when groups is non-null. If 'FALSE' (the
          default), bars for different values of the grouping variable
          are drawn side by side, otherwise they are stacked. 

  groups: optional grouping variable

col, border, lty, lwd: Graphical parameters for the bars. By default,
          the trellis parameter 'plot.polygon' is used if there is no
          grouping variable, otherwise 'superpose.polygon' is used. 
          'col' gives the fill color, 'border' the border color, and
          'lty' and 'lwd' the line type and width of the borders. 

     ...: extra arguments will be accepted but ignored 

Details:

     A barchart is drawn in the panel. Note that most arguments
     controlling the display can be supplied to the high-level
     'barchart' call directly.

Author(s):

     Deepayan Sarkar Deepayan.Sarkar@R-project.org

See Also:

     'barchart'

