bubble {sp}R Documentation

Create a bubble plot of spatial data

Description

Create a bubble plot of spatial data, with options for bicolour residual plots (xyplot wrapper)

Usage

bubble(obj, zcol = 1, ..., fill = TRUE, maxsize = 3, do.sqrt = TRUE, pch, 
        col = c(2,3), key.entries = quantile(data[,zcol]), main, 
        identify = FALSE, labels = row.names(data.frame(obj)), key.space = "right",
        scales = list(draw = FALSE), xlab = NULL, ylab = NULL, panel = panel.bubble,
        sp.layout = NULL)

Arguments

obj object of, or extending, class SpatialPointsDataFrame or SpatialGridDataFrame, see coordinates or SpatialPointsDataFrame; the object knows about its spatial coordinates
zcol z-variable column name, or column number after removing spatial coordinates from x@data: 1 refers to the first non-coordinate column
fill logical; if TRUE, filled circles are plotted (pch = 16), else open circles (pch = 1); the pch argument overrides this
maxsize cex value for largest circle
do.sqrt logical; if TRUE the plotting symbol area (sqrt(diameter)) is proportional to the value of the z-variable; if FALSE, the symbol size (diameter) is proportional to the z-variable
pch plotting character
col colours to be used; numeric vector of size two: first value is for negative values, second for positive values.
key.entries the values that will be plotted in the key; by default the five quantiles min, q.25, median q.75, max
main main plotting title
identify logical; if true, regular plot is called instead of xyplot, and followed by a call to identify().
labels labels argument passed to plot if identify is TRUE
... arguments, passed to xyplot, or plot if identification is required.
key.space location of the key
scales scales argument as passed to xyplot
xlab x-axis label
ylab y-axis label
panel panel function used
sp.layout possible layout items; see spplot

Value

returns (or plots) the bubble plot; if identify is TRUE, returns the indexes (row numbers) of identified points.

Author(s)

Edzer J. Pebesma

References

See Also

xyplot, mapasp, identify

Examples

data(meuse)
coordinates(meuse) <- c("x", "y") # promote to SpatialDataFrame
bubble(meuse, "cadmium", maxsize = 2.5, main = "cadmium concentrations (ppm)", 
    key.entries = 2^(-1:4))
bubble(meuse, "zinc", main = "zinc concentrations (ppm)",
    key.entries =  100 * 2^(0:4))
[Package sp version 0.9-12 Index]