R: Test Whether a Window is Convex

is.convex {spatstat.geom} | R Documentation

## Test Whether a Window is Convex

### Description

Determines whether a window is convex.

### Usage

      is.convex(x)

### Arguments

`x` | Window (object of class `"owin"`).

### Details

If `x` is a rectangle, the result is TRUE.

If `x` is polygonal, the result is TRUE if `x` consists of a single polygon and this polygon is equal to the minimal convex hull of its vertices computed by `chull`.

If `x` is a mask, the algorithm first extracts all boundary pixels of `x` using `vertices`. Then it computes the (polygonal) convex hull K of the boundary pixels. The result is TRUE if every boundary pixel lies within one pixel diameter of an edge of K.

### Value

Logical value, equal to `TRUE` if `x` is convex.

### Author(s)

Adrian Baddeley Adrian.Baddeley@curtin.edu.au

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

### See Also

`owin`, `convexhull.xy`, `vertices`

[Package spatstat.geom version 2.3-2 Index]