registry_KNN_dist {ARPALData}R Documentation

Identifies the K-nearest-neighbours (stations) to all the monitoring sites included in a given ARPALdf registry data.frame. The neighbours are identified computing the Euclidean distance among the sites' coordinates.

Description

# For each element included in reg_X, it dentifies the k-nearest neighbours locations (among those included in reg_Y) according to an Euclidean distance metric. reg_X and reg_Y must be two 'ARPALdf' objects obtained using get_ARPA_Lombardia_xxx_registry'.

Usage

registry_KNN_dist(reg_X, reg_Y, k = 1)

Arguments

reg_X

Dataset of class 'ARPALdf' containing the stations list obtained as registry (from 'get_ARPA_Lombardia_xxx_registry' command). The object must contain the following colums: 'IDStation','NameStation','Longitude' and 'Latitude'.

reg_Y

Dataset of class 'ARPALdf' containing the stations list obtained as registry (from 'get_ARPA_Lombardia_xxx_registry' command). The object must contain the following colums: 'IDStation','NameStation','Longitude' and 'Latitude'.

k

Integer value. Represents the number of neighbours the user wants to identify.

Value

A data.frame object having the same length of reg_X. For each row (stations in reg_X) it contains the name and the IDStation code for the k-nearest neighbours.

Examples

library(tidyverse)
regAQ <- get_ARPA_Lombardia_AQ_registry()
regAQ <- regAQ %>% filter(Pollutant %in% c("PM10","Ammonia"))
regW <- get_ARPA_Lombardia_W_registry()
registry_KNN_dist(regAQ,regW,k=2)


[Package ARPALData version 1.2.3 Index]