Quake Visualisations (QV)

QV_01_Scrape_Locations.R

#PRELIMINARIES:
  install.packages("pacman")
  pacman::p_load(XML,rvest,magrittr,RCurl,stringi)

#Step 1: Establish location names and addresses for Harvey Norman Electrical stores

#draw in address locations from website:
  url<-"http://www.harveynorman.co.nz/store-finder.html"
  rvest_target<-read_html(url)
  rvest_table_nodes <- html_nodes(rvest_target,"p.address ")
  addresses<-html_text(rvest_table_nodes,TRUE)

  ##Note - https://cran.r-project.org/web/packages/rvest/vignettes/selectorgadget.html
  ## This link contains details on how to use the SelectorGadget tool to identify CSS markers on webpages
  
  #remove nearly all html carriage returns and formatting
  addresses<-strsplit(addresses," \r\n\t")

#write output to a matrix in which view map and other spaces are removed:
  size.reqd<-length(addresses)
  output.addresses<- matrix(nrow=size.reqd,ncol=1)
  for (i in 1:length(addresses)){
    output.addresses[i]<-unlist(strsplit(paste0(unlist(addresses[i]),sep = ", ", collapse = ""),"View Map,"))
  }
  print(output.addresses)

#scan output for errors then manually correct: NB rows 2 and 37
  #row 2 first: 
    temp<-paste0(unlist(strsplit(output.addresses[2],"\r\n\t")),sep = ", ", collapse = "")
    nchar(temp) #66 characters long, so retain all but last two to purge extra comma 
    output.addresses[2]= substr(temp,start=1, stop=64)
    rm(temp)
  #then correct row 37: 
    temp<-paste0(unlist(strsplit(output.addresses[37],"\r\n")),sep = ", ", collapse = "")
    nchar(temp) #66 characters long, so retain all but last two to purge extra comma 
    output.addresses[37]= substr(temp,start=1, stop=46)
    rm(temp)