AQuadtree (version 1.0.4)

joinAQuadtrees: Join two AQuadtree objects from the same area, to compare their data

Description

Given two objects of class AQuadtree for the same area, wich, for instance, may contain data from two different periods, joinAQuadtrees returns a new object of class AQuadtree with the common zones at the lowest shared level, summarising the data from both AQuadtrees.

Usage

joinAQuadtrees(qt1, qt2, withResiduals = FALSE, mean.1 = NULL, mean.2 = NULL)

Value

AQuadtree with the information of the two given objects summarised at the lowest level shared by both objects.

Arguments

qt1

object of class "AQuadtree" containing the first object to join.

qt2

object of class "AQuadtree" containing the second object to join.

withResiduals

logical indicating if residual cells should be maintained (TRUE) or not (FALSE, default).

mean.1

character or character vector specifying the columns in the first AQuadtreeto which a weighted mean should be computed. By default the aggregation function used is sum.

mean.2

character or character vector specifying the columns in the first AQuadtreeto which a weighted mean should be computed. By default the aggregation function used is sum.

Details

The function joinAQuadtrees creates a new AQuadtree object from two given AQuadtree objects with data from the same area. The data of the two given objects is summarised at the smallest possible cells shared by both given objects. All the input data is maintained on the new created object. This function can be used to join the different attributes from the same area or information from different periods.

Examples

data("CharlestonPop")
CharlestonPop.AQT_1<-AQuadtree(CharlestonPop, layers = 2)
CharlestonPop.AQT_2<-AQuadtree(CharlestonPop, colnames="sex",
       thresholdField=c("sex.male", "sex.female"), layers = 2)
CharlestonPop.AQT_1_2<-joinAQuadtrees(CharlestonPop.AQT_1, CharlestonPop.AQT_2)

if (FALSE) {
## non AQuadtree objects
joinAQuadtrees(CharlestonPop, CharlestonCensusTracts)
}