
Inspecting and Exploring Data 91
rad
Density
0.00 0.10 0.20 0.30
0 2 4 6 8 10
0.0 0.1 0.2 0.3
0.0 0.2 0.4 0.6 0.8 1.
rad
Cumulative probability
Figure 4.11. Histogram (Left) and cumulative distribution function (Right) of terrain elevation in
the Beilschmie dia data.
graphics. The function locator records the spatial locations of the mouse when the left mouse
button is clicked.
The R generic function identify allows the user to select da ta points in an existing plot,
and read information about th e m. Methods for identify are provided in spatstat, including
identify.ppp. After typing
> plot(amacrine)
> identify(amacrine)
the user can click on any point