spatstat.geom (version 2.1-0)

simplify.owin: 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.

Value

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

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.

See Also

owin

Examples

# NOT RUN {
  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))
# }