R: Hexagonal Grid or Tessellation

hextess {spatstat.geom} | R Documentation

## Hexagonal Grid or Tessellation

### Description

Construct a hexagonal grid of points, or a hexagonal tessellation.

### Usage

    hexgrid(W, s, offset = c(0, 0), origin=NULL, trim = TRUE)

    hextess(W, s, offset = c(0, 0), origin=NULL, trim = TRUE)

### Arguments

`W` | Window in which to construct the hexagonal grid or tessellation. An object of class `"owin"`.
`s` | Side length of hexagons. A positive number.
`offset` | Numeric vector of length 2 specifying a shift of the hexagonal grid. See Details.
`origin` | Numeric vector of length 2 specifying the initial origin of the hexagonal grid, before the offset is applied. See Details.
`trim` | Logical value indicating whether to restrict the result to the window `W`. See Details.

### Details

`hexgrid` constructs a hexagonal grid of points on the window `W`. If `trim=TRUE` (the default), the grid is intersected with `W` so that all points lie inside `W`. If `trim=FALSE`, then we retain all grid points which are the centres of hexagons that intersect `W`.

`hextess` constructs a tessellation of hexagons on the window `W`. If `trim=TRUE` (the default), the tessellation is restricted to the interior of `W`, so that there will be some fragmentary hexagons near the boundary of `W`. If `trim=FALSE`, the tessellation consists of all hexagons which intersect `W`.

The points of `hexgrid(...)` are the centres of the tiles of `hextess(...)` in the same order.

In the initial position of the grid or tessellation, one of the grid points (tile centres) is placed at the `origin`, which defaults to the midpoint of the bounding rectangle of `W`. The grid can be shifted relative to this origin by specifing the `offset`.

### Value

The value of `hexgrid` is a point pattern (object of class `"ppp"`).

The value of `hextess` is a tessellation (object of class `"tess"`).

### 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

`tess`

`hexagon`

### Examples

      if(interactive()) {
        W <- Window(chorley)
        s <- 0.7
      } else {
        W <- letterR
        s <- 0.3
      }
      plot(hextess(W, s))
      plot(hexgrid(W, s), add=TRUE)

[Package spatstat.geom version 2.2-0 Index]