geoR (version 1.9-4)

dup.coords: Locates duplicated coordinates

Description

This funtions takes an object with 2-D coordinates and returns the positions of the duplicated coordinates. Also sets a method for duplicated

Usage

dup.coords(x, ...)
# S3 method for default
dup.coords(x, ...)
# S3 method for geodata
dup.coords(x, incomparables, ...)
# S3 method for geodata
duplicated(x, incomparables, ...)

Value

Function and methods returns NULL if there are no duplicates locations.

Otherwise, the default method returns a list where each component is a vector with the positions or the rownames, if available, of the duplicates coordinates.

The method for geodata returns a data-frame with rownames equals to the positions of the duplicated coordinates, the first column is a factor indicating duplicates and the remaning are output of as.data.frame.geodata.

Arguments

x

a two column numeric matrix or data frame.

incomparables

unused. Just for compatibility with the generic function duplicated.

...

arguments passed to sapply. If simplify = TRUE (default) results are returned as an array if possible (when the number of replicates are the same at each replicated location)

Author

Paulo Justiniano Ribeiro Jr.
Peter J. Diggle .

See Also

as.geodata for the definition of geodata class, duplicated for the base function to identify duplicated values and jitterDupCoords for a function which jitters duplicated coordinates.

Examples

## simulating data
dt <- grf(30, cov.p=c(1, .3)) 
## "forcing" some duplicated locations
dt$coords[4,] <- dt$coords[14,] <- dt$coords[24,] <- dt$coords[2,]
dt$coords[17,] <- dt$coords[23,] <- dt$coords[8,]
## output of the method for geodata
dup.coords(dt)
## which is the same as a method for duplicated()
duplicated(dt)
## the default method:
dup.coords(dt$coords)