R: Approximate a Polygon by a Simpler Polygon

simplify.owin {spatstat} | R Documentation

## Approximate a Polygon by a Simpler Polygon

### Description

Given a polygonal window, this function finds a simpler polygon that approximates it.

### Usage

    simplify.owin(W, dmin)

### Arguments

`W` | The polygon which is to be simplied. An object of class `"owin"`.
`dmin` | Numeric value. The smallest permissible length of an edge.

### Details

This function simplifies a polygon `W` by recursively deleting the shortest edge of `W` until all remaining edges are longer than the specified minimum length `dmin`, or until there are only three edges left.

The argument `W` must be a window (object of class `"owin"`). It should be of type `"polygonal"`. If `W` is a rectangle, it is returned without alteration.

The simplification algorithm is not yet implemented for binary masks. If `W` is a mask, an error is generated.

### Value

Another window (object of class `"owin"`) of type `"polygonal"`.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au, Rolf Turner r.turner@auckland.ac.nz and Ege Rubak rubak@math.aau.dk.

### See Also

`owin`

### Examples

      plot(letterR, col="red")
      plot(simplify.owin(letterR, 0.3), col="blue", add=TRUE)

      W <- Window(chorley)
      plot(W)
      WS <- simplify.owin(W, 2)
      plot(WS, add=TRUE, border="green")
      points(vertices(WS))

[Package spatstat version 1.54-0 Index]