.BG
.VE $Header: /usr/s/current/s/.help/RCS/symbols,v 1.6 86/10/07 15:42:26 rab Exp $
.FN symbols
.TL
symbols: Draw Symbols on a Plot
.CS
symbols(x, y, circles=, squares=, rectangles=, stars=,
    thermometers=, boxplots=, add, inches)
.PP
.AG x,y
coordinates of centers of symbols. A structure containing
components named `x' and `y' can also be given.
Missing values (NAs) are allowed.
.AG circles=
the radii of the circles.
.AG squares=
the lengths of the sides of the squares.
.AG rectangles=
matrix whose two columns give widths and heights of
rectangles.
.AG stars=
a matrix with `n' columns, where `n' is the number of points
to a star.  The matrix should be scaled from 0 to 1.
.AG thermometers=
a matrix with 3 or 4 columns.
The first two columns give the width and height of the thermometer symbols.
The third and fourth columns
give the fraction of space at the top and bottom of the thermometer that
should be left blank.  If there is no fourth column, the
filled region starts from the bottom.
.AG boxplots=
a matrix with 5 columns.
The first two columns give the width and height of the boxplot symbols.
The third and fourth columns give the lengths of the whiskers extending
from the top and bottom of the box.
The fifth column gives the fraction of the way from bottom to top
that the "median" line crosses the box.
.AG add
logical flag. If FALSE (default), a new plot is set up.  If
TRUE, symbols are added to the existing plot.
.AG inches
if FALSE, the symbol parameters are interpreted as being in
units of `x' and `y'.  If TRUE (default), the symbols are
scaled so that the largest symbol is one inch in size.  If a
number is given, the parameters are scaled so that `inches'
is the size of the largest symbol in inches.
.PP
Graphical parameters may also be given as arguments to this function
(see `par').
.PP
Only one of the arguments `circles=', `squares=', `rectangles=',
`stars=', `thermometers=' or `boxplots=' may be given.
Missing values (NAs) are allowed in these arguments; except for
`stars', any NAs cause the symbol to be omitted from the plot.
For `stars', NAs cause the corresponding radial line to be omitted.
.EX
symbols(x,y,circle=radii,inches=5)
      #  largest circle has radius 5 inches

p <- ?col(parm,range)  #find min/max of each column of parm
pscale <- scale(parm,center=p[1,],scale=p[2,]-p[1,])  # scale to 0-1
symbols(x,y,stars=pscale) # plot stars
.KW plot*
.KW aplot*
.KW hplot*
.WR
