spatstat.geom (version 3.3-3)

tileindex: Determine Which Tile Contains Each Given Point

Description

Given a tessellation and a list of spatial points, determine which tile of the tessellation contains each of the given points.

Usage

tileindex(x, y, Z)

Value

A factor, of the same length as x and y, whose levels are the names of the tiles of Z.

Arguments

x,y

Spatial coordinates. Numeric vectors of equal length. (Alternatively y may be missing and x may be an object containing spatial coordinates).

Z

A tessellation (object of class "tess").

Author

Adrian Baddeley , Rolf Turner and Ege Rubak

Details

This function determines which tile of the tessellation Z contains each of the spatial points with coordinates (x[i],y[i]).

The result is a factor, of the same length as x and y, indicating which tile contains each point. The levels of the factor are the names of the tiles of Z. Values are NA if the corresponding point lies outside the tessellation.

See Also

cut.ppp and split.ppp to divide up the points of a point pattern according to a tessellation.

as.function.tess to create a function whose value is the tile index.

Examples

  X <- runifrect(7)
  V <- dirichlet(X)
  tileindex(0.1, 0.4, V)
  tileindex(list(x=0.1, y=0.4), Z=V)
  tileindex(X, Z=V)