Quake Visualisations (QV)

QV_02_Assign_LatLong.R

#PRELIMINARIES:
pacman::p_load(XML)

#recode as data frame :
output.addresses.df<-data.frame(c(output.addresses))
output.addresses.df<-cbind(output.addresses.df,long=1,lat=2)


#assign long/lat
for (i in 1:length(output.addresses)){
  addr <-output.addresses[i]
  url = paste('http://maps.google.com/maps/api/geocode/xml?address=', addr,'&sensor=false',sep='')  # construct the URL
  doc = xmlTreeParse(url) 
  root = xmlRoot(doc) 
  output.addresses.df[i,2] = xmlValue(root[['result']][['geometry']][['location']][['lng']]) 
  output.addresses.df[i,3] = xmlValue(root[['result']][['geometry']][['location']][['lat']]) 
}
print(output.addresses.df)

#row 35 and 38 have problems - 35 is returning something with long/lats that are way off; and 38 is throwing an error.  
#Manually searching google maps shows that the value for this row, needs a slight change.  Overwriting using the following
#approach solves the problem....

addr <-" Cnr West Street & Moore Street, Ashburton"
url = paste('http://maps.google.com/maps/api/geocode/xml?address=', addr,'&sensor=false',sep='')  # construct the URL
doc = xmlTreeParse(url) 
root = xmlRoot(doc) 

output.addresses.df[35,2] = xmlValue(root[['result']][['geometry']][['location']][['lng']]) 
output.addresses.df[35,3] = xmlValue(root[['result']][['geometry']][['location']][['lat']]) 

addr <-"Cnr Maclaggan Street & Rattray Street, Dunedin"
url = paste('http://maps.google.com/maps/api/geocode/xml?address=', addr,'&sensor=false',sep='')  # construct the URL
doc = xmlTreeParse(url) 
root = xmlRoot(doc) 

output.addresses.df[38,2] = xmlValue(root[['result']][['geometry']][['location']][['lng']]) 
output.addresses.df[38,3] = xmlValue(root[['result']][['geometry']][['location']][['lat']]) 

#all locations assigned now:
print(output.addresses.df)

#format long lat as numbers (needed later)
colnames(output.addresses.df)<-c("Address","long","lat")
output.addresses.df$Address<-as.character(output.addresses.df$Address)
output.addresses.df$long<-as.numeric(output.addresses.df$long)
output.addresses.df$lat<-as.numeric(output.addresses.df$lat)