spatstat (version 1.3-2)

centroid.owin: Centroid of a window

Description

Computes the centroid (centre of mass) of a window

Usage

centroid.owin(w)

Arguments

w

A window

Value

• A list with components x, y giving the coordinates of the centroid of the window w.

Details

The centroid of the window w is computed. The centroid (``centre of mass'') is the point whose $x$ and $y$ coordinates are the mean values of the $x$ and $y$ coordinates of all points in the window.

The argument w should be a window (an object of class "owin", see owin.object for details) or can be given in any format acceptable to as.owin().

See Also

owin, as.owin

Examples

library(spatstat)
  w <- owin(c(0,1),c(0,1))
  centroid.owin(w) 
  # returns 0.5, 0.5

  data(demopat)
  w <- demopat$window
  # an irregular window
  plot(w)
  # plot the window
  points(centroid.owin(w))
  # mark its centroid

  wapprox <- as.mask(w)
  # pixel approximation of window
  points(centroid.owin(wapprox))
  # should be indistinguishable
  <testonly>centroid.owin(w)
  centroid.owin(wapprox)</testonly>