# hextess: Hexagonal Grid or Tessellation In spatstat: Spatial Point Pattern Analysis, Model-Fitting, Simulation, Tests

## Description

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

## Usage

 ```1 2 3``` ```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"`).

\spatstatAuthors

## See Also

`tess`

`hexagon`

## Examples

 ```1 2 3 4 5 6 7 8 9``` ``` if(interactive()) { W <- Window(chorley) s <- 0.7 } else { W <- letterR s <- 0.3 } plot(hextess(W, s)) plot(hexgrid(W, s), add=TRUE) ```

### Example output

```Loading required package: nlme
Loading required package: rpart

spatstat 1.52-1       (nickname: 'Apophenia')
For an introduction to spatstat, type 'beginner'
```

spatstat documentation built on June 15, 2018, 9:04 a.m.