spatstat.geom (version 3.2-8)

convexhull.xy: Convex Hull of Points

Description

Computes the convex hull of a set of points in two dimensions.

Usage

convexhull.xy(x, y=NULL)

Value

A window (an object of class "owin").

Arguments

x

vector of x coordinates of observed points, or a 2-column matrix giving x,y coordinates, or a list with components x,y giving coordinates (such as a point pattern object of class "ppp".)

y

(optional) vector of y coordinates of observed points, if x is a vector.

Author

Adrian Baddeley

and Rolf Turner

Details

Given an observed pattern of points with coordinates given by x and y, this function computes the convex hull of the points, and returns it as a window.

See Also

owin, as.owin, convexhull, bounding.box.xy, ripras

Examples

  x <- runif(30)
  y <- runif(30)
  w <- convexhull.xy(x,y)
  plot(owin(), main="convexhull.xy(x,y)", lty=2)
  plot(w, add=TRUE)
  points(x,y)

  X <- runifrect(30)
  plot(X, main="convexhull.xy(X)")
  plot(convexhull.xy(X), add=TRUE)