R: Differences between neighbours lists

diffnb {spdep} | R Documentation

## Differences between neighbours lists

### Description

The function finds differences between lists of neighbours, returning a `nb` neighbour list of those found

### Usage

    diffnb(x, y, verbose=NULL)

### Arguments

`x` | an object of class `nb`
`y` | an object of class `nb`
`verbose` | default NULL, use global option value; report regions ids taken from object attribute "region.id" with differences

### Value

A neighbours list with class `nb`

### Author(s)

Roger Bivand Roger.Bivand@nhh.no

### Examples

    example(columbus)
    coords <- coordinates(columbus)
    rn <- sapply(slot(columbus, "polygons"), function(x) slot(x, "ID"))
    knn1 <- knearneigh(coords, 1)
    knn2 <- knearneigh(coords, 2)
    nb1 <- knn2nb(knn1, row.names=rn)
    nb2 <- knn2nb(knn2, row.names=rn)
    diffs <- diffnb(nb2, nb1)
    plot(columbus, border="grey")
    plot(nb1, coords, add=TRUE)
    plot(diffs, coords, add=TRUE, col="red", lty=2)
    title(main="Plot of first (black) and second (red)\nnearest neighbours")

[Package spdep version 0.6-13 Index]