Add a Legend to a Hexbin Plot

Plots the legend for the plot method of hexbin. Provides a legend indicating the count representations.

Usage

grid.hexlegend(legend, ysize, lcex, inner, style = ,
       minarea = 0.05, maxarea = 0.8, mincnt = 1, maxcnt, trans = NULL,
     inv = NULL, colorcut, density = NULL, border = NULL, pen = NULL,
     colramp = function(n) { LinGray(n,beg = 90,end = 15) },
           leg.unit = "native")

Arguments

legend: positive number giving width of the legend in inches.
ysize: height of legend in inches
lcex: the characters expansion size for the text in the legend, see par(cex=).
inner: the inner diameter of a hexagon in inches.
style: the hexagon style; see grid.hexagons.
minarea, maxarea: fraction of the cell area for the lowest and largest count, respectively.
mincnt, maxcnt: minimum and maximum count accepted in plot.
trans: a transformation function for the counts such as sqrt.
inv: the inverse transformation function.
colorcut: numeric vector of values covering [0, 1] the determine hexagon color classes boundaries and hexagon legend size boundaries.
border: argument for polygon(). Draw the border for each hexagon.
density: argument for polygon() filling. A 0 causes the polygon not to be filled.
pen: color argument used for polygon(col = .). Determines the color with which the polygon will be filled.
colramp: function accepting an integer n as an argument and returning n colors.
leg.unit: unit to use

Details

The plot method for hexbin objects calls this function to produce a legend by setting the graphics parameters, so hex.legend itself is not a standalone function.

The legend function is preliminary. Later version will include refinements and handle extreme cases (small and large) for cell size and counts.

See the Details section of grid.hexagons's help page.

Value

This function does not return any value.

References

see in grid.hexagons.

Author

Dan Carr <[email protected]>

ported by Nicholas Lewin-Koh <[email protected]>

Examples

## Not a stand alone function; typically only called from plot.hexbin()


if (FALSE) { # \dontrun{
  grid.hexlegend(legend = 2, ysize = 1,lcex=8,inner=0.2,
                 maxcnt = 100, colorcut = c(0.5,0.5))
} # }