Plot with repeated symbols by size

Plots a set of (x,y) data with repeated points denoted by larger symbol sizes

sizeplot(x, y, scale=1, pow=0.5, powscale=TRUE, size=c(1,4), add=FALSE, ...)

Arguments

x

x coordinates of data

y

y coordinates of data

scale

scaling factor for size of symbols

pow

power exponent for size of symbols

powscale

(logical) use power scaling for symbol size?

size

(numeric vector) min and max size for scaling, if powscale=FALSE

add

(logical) add to an existing plot?

...

other arguments to plot() or points()

Details

Most useful for plotting (e.g.) discrete data, where repeats are likely. If all points are repeated equally, gives a warning. The size of a point is given by \(scale*n^pow\), where n is the number of repeats, if powscale is TRUE, or it is scaled between size[1] and size[2], if powscale is FALSE.

Value

A plot is produced on the current device, or points are added to the current plot if add=TRUE.

Author

Ben Bolker

See also

symbols

Examples

 x <- c(0.1,0.1,0.1,0.1,0.1,0.2,0.2,0.2,0.2,0.3,0.3)
 y <- c( 1,  1,  1,  1,  2,  2,  2,  3,  3,  4,  5 )
 plot(x,y)

 sizeplot(x,y)

 sizeplot(x,y,pch=2)