grid.yaxis               package:grid               R Documentation

Draw a Y-Axis

Description:

     These functions create and draw a y-axis.

Usage:

     grid.yaxis(at = NULL, label = TRUE, main = TRUE,
                edits = NULL, name = NULL,
                gp = gpar(), draw = TRUE, vp = NULL)

     yaxisGrob(at = NULL, label = TRUE, main = TRUE,
               edits = NULL, name = NULL,
               gp = gpar(), vp = NULL)

Arguments:

      at: A numeric vector of y-value locations for the tick marks.

   label: A logical value indicating whether to draw the labels on the
          tick marks, or an expression or character vector which
          specify the labels to use.  If not logical, must be the same
          length as the 'at' argument.

    main: A logical value indicating whether to draw the axis at the
          left ('TRUE') or at the right ('FALSE') of the viewport.

   edits: A gEdit or gEditList containing edit operations to apply (to
          the children of the axis) when the axis is first created and
          during redrawing whenever 'at' is 'NULL'. 

    name: A character identifier. 

      gp: An object of class 'gpar', typically the output from a call
          to the function 'gpar'.  This is basically a list of
          graphical parameter settings.

    draw: A logical value indicating whether graphics output should be
          produced.

      vp: A Grid viewport object (or 'NULL').

Details:

     Both functions create a yaxis grob (a graphical object describing
     a yaxis), but only 'grid.yaxis' draws the yaxis (and then only if
     'draw' is 'TRUE').

Value:

     A yaxis grob.  'grid.yaxis' returns the value invisibly.

Children:

     If the 'at' slot of an xaxis grob is not 'NULL' then the xaxis
     will have the following children:

     major representing the line at the base of the tick marks.

     ticks representing the tick marks.

     labels representing the tick labels.

     If the 'at' slot is 'NULL' then there are no children and ticks
     are drawn based on the current viewport scale.

Author(s):

     Paul Murrell

See Also:

     Grid, 'viewport', 'grid.xaxis'

