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Last data update: 2014.03.03

R: Dividing chain; default method.

divchain.default

R Documentation

Dividing chain; default method.

Description

Create the “dividing chain” of the Dirchlet tesselation of a given set of points having distinguishing (categorical) “weights”. This dividing chain consists of those edges of Dirichlet tiles which separate points having different values of the given weights.

Usage

  ## Default S3 method:
divchain(x, y, z, ...)

Arguments

`x,y`	These provide the coordinates of the set of points being tesselated. Argument `x` may be a data frame or a list, in particular one of class `ppp`. (See the `spatstat` package.) For a full description see the discussion of these arguments in the help for `deldir()`.
`z`	A factor specifying “auxiliary” values or “weights” If this argument is left `NULL` then it is extracted, if possible, from the components of `x`. See `deldir()` for further details.
`...`	Other arguments to be passed to `deldir`.

Value

An object of class divchain. See divchain.deldir() for details.

Note

This function was created in response to a question asked on stackoverflow.com by a user named “Dan”.

Author(s)

Rolf Turner r.turner@auckland.ac.nz

Examples

   set.seed(42)
   x    <- runif(50)
   y    <- runif(50)
   z    <- factor(kmeans(cbind(x,y),centers=4)$cluster)
   dcxy <- divchain(x,y,z,rw=c(0,1,0,1))