R: Locates duplicated coordinates

dup.coords {geoR} | R Documentation

## 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, ...)
    ## Default S3 method:
    dup.coords(x, ...)
    ## S3 method for class 'geodata'
    dup.coords(x, incomparables, ...)
    ## S3 method for class 'geodata'
    duplicated(x, incomparables, ...)

### 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)

### 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`.

### Author(s)

Paulo Justiniano Ribeiro Jr. paulojus@leg.ufpr.br
Peter J. Diggle p.diggle@lancaster.ac.uk.

### 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)

[Package geoR version 1.7-5.2 Index]