distmap {spatstat.geom}

Distance Map

Description

Compute the distance map of an object, and return it as a pixel image. Generic.

Usage

  distmap(X, ...)

Arguments

X

Any suitable dataset representing a two-dimensional object, such as a point pattern (object of class "ppp"), a window (object of class "owin") or a line segment pattern (object of class "psp").

...

Arguments passed to as.mask to control pixel resolution.

Details

The “distance map” of a set of points A is the function f whose value f(x) is defined for any two-dimensional location x as the shortest distance from x to A.

This function computes the distance map of the set X and returns the distance map as a pixel image.

This is generic. Methods are provided for point patterns (distmap.ppp), line segment patterns (distmap.psp) and windows (distmap.owin).

Value

A pixel image (object of class "im") whose grey scale values are the values of the distance map.

Author(s)

Adrian Baddeley [e-mail] and Rolf Turner [e-mail]

See Also

distmap.ppp, distmap.psp, distmap.owin, distfun

Examples

  U <- distmap(cells)
  V <- distmap(letterR)
  if(interactive()) {
  plot(U)
  plot(V)
  }