BayesX (version 0.2-3)

Interface between sp and bnd format: Convert sp and bnd format into each other

Description

Convert geographical information objects of class "SpatialPolygons" (or specializations) from R-package sp to objects of class "bnd" from R-package BayesX and vice versa.

Usage

sp2bnd(spObject, regionNames, height2width, epsilon)
bnd2sp(bndObject)

Value

Equivalent object in the other format.

See Also

nb2gra, gra2nb for conversion between the neighborhood structure formats and read.bnd, write.bnd for the interface to the BayesX files.

Examples

## bnd to sp:
germany <- read.bnd(system.file("examples/germany2001.bnd", package="BayesX"))
spGermany <- bnd2sp(germany)

## plot the result together with the neighborhood graph
library(sp)
plot(spGermany)
library(spdep)
nbGermany <- poly2nb(spGermany)
plot(nbGermany, coords=coordinates(spGermany), add=TRUE)

## example with one region inside another
spExample <- spGermany[c("7211", "7235"), ]
plot(spExample)
plot(poly2nb(spExample), coords=coordinates(spExample), add=TRUE)

## now back from sp to bnd:
bndGermany <- sp2bnd(spGermany)
drawmap(map=bndGermany)

## compare names and number of polygons
stopifnot(identical(names(bndGermany),
                    names(germany)),
          identical(length(bndGermany),
                    length(germany)))

## compare contains-relations
surrounding <- attr(bndGermany, "surrounding")
whichInner <- which(sapply(surrounding, length) > 0L)
bndContainsData <- data.frame(inner=names(bndGermany)[whichInner],
                              outer=unlist(surrounding))

surrounding <- attr(germany, "surrounding")
whichInner <- which(sapply(surrounding, length) > 0L)
originalContainsData <- data.frame(inner=names(germany)[whichInner],
                                   outer=unlist(surrounding))

stopifnot(all(bndContainsData[order(bndContainsData$inner), ] ==
              originalContainsData[order(originalContainsData$inner), ]))