spatstat.geom (version 3.2-8)

uniquemap.ppp: Map Duplicate Entries to Unique Entries

Description

Determine whether points in a point pattern are duplicated, choose a unique representative for each set of duplicates, and map the duplicates to the unique representative.

Usage

uniquemap(x)
# S3 method for ppp
uniquemap(x)
# S3 method for lpp
uniquemap(x)
# S3 method for ppx
uniquemap(x)

Value

An integer vector.

Arguments

x

A point pattern (object of class "ppp", "lpp", "pp3" or "ppx").

Author

Adrian Baddeley , Rolf Turner and Ege Rubak .

Details

The function uniquemap is generic, with methods for point patterns and data frames.

This function determines whether any points of x are duplicated, and constructs a mapping of the indices of x so that all duplicates are mapped to a unique representative index.

The result is an integer vector u such that u[j] = i if the points x[i] and x[j] are identical and point i has been chosen as the unique representative. The entry u[i] = i means either that point i is unique, or that it has been chosen as the unique representative of its equivalence class.

See Also

unique.ppp, duplicated.ppp, uniquemap.default

Examples

  Y <- runifrect(4)
  X <- Y[c(1,2,3,4,2,1)]
  uniquemap(X)