dots: Make a dot-density map

In terra: Spatial Data Analysis

Make a dot-density map

Description

Create the dots for a dot-density map and add these to the current map. Dot-density maps are made to display count data. For example of population counts, where each dot represents n persons. The dots are returned as a SpatVector. It there is an active graphics device, the dots are added to it with points.

Usage

## S4 method for signature 'SpatVector'
dots(x, field, size,  ...)

Arguments

x	SpatVector
field	character of numeric indicating field name. Or numeric vector of the same length as x
size	positive number indicating the number of cases associated with each dot
...	graphical arguments passed to points

Value

SpatVector (invisibly)

See Also

plot, cartogram, points

Examples

 
f <- system.file("ex/lux.shp", package="terra")
v <- vect(f)
v$population <- 1000*(1:12)^2
plot(v, lwd=3, col="light gray", border="white")
d <- dots(v, "population", 1000, col="red", cex=.75)
lines(v)
d

terra documentation built on Oct. 14, 2024, 5:07 p.m.