R: Convex Hull of Points

convexhull.xy {spatstat} | R Documentation

## Convex Hull of Points

### Description

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

### Usage

    convexhull.xy(x, y=NULL)

### 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.

### 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.

### Value

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

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

and Rolf Turner r.turner@auckland.ac.nz

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

[Package spatstat version 1.63-3 Index]