Problems with reverse geocoding loops with latitude longitude co-ordinates using googleway: r gives the same results for different co-ordinates

Question

Here is my sample dataset (called origAddress):

lat  lng
1.436316  103.8299
1.375093  103.8516
1.369347  103.8398
1.367353  103.8426

I have many more rows of latitude and longitude numbers (330) and I would like to find the address. I have used this for loop to do that:

for(i in 1:nrow(origAddress))
{
  # Print("Working...")
  result <- google_reverse_geocode(location = c(origAddress$lat[i],origAddress$lng[i]), 
  key = key,
  location_type = "rooftop")
  if(is.null(result) || length(dim(result)) < 2 || !nrow(result)) next
  origAddress$venadd <- geocode_address(result)
}

It works for the first three or four rows but then returns the same address as the first row although the latitude and longitude numbers are definitely different. I have looked at other stackoverflow questions(here) and tried to copy their approach with similar bad results.

Please help!

This line: origAddress$venadd <- geocode_address(result) is overwriting the entire column with the last result found. — Dave2e, Apr 30 '18 at 17:52
Thanks @Dave2e - I have also tried origAddress$venadd[i], any other suggestions? — Neel Rajani, Apr 30 '18 at 22:22

Dave2e · Accepted Answer · 2018-05-01T23:29:24.783

It looks like the calls to google_geocode can return more than one address for each lat/longitude pair thus you could be overwriting your data in the output data frame.
Also, I am not sure your if statement is evaluating properly.
Here is my attempt on your problem:

library(googleway)

origAddress<-read.table(header = TRUE, text = "lat  lng
1.436316  103.8299
1.375093  103.8516
1.369347  103.8398
1.367353  103.8426")

#add the output column
origAddress$venadd<-NA

for(i in 1:nrow(origAddress))
{
  # Print("Working...")
  result <- google_reverse_geocode(location = c(origAddress$lat[i],origAddress$lng[i]), 
                                   key=key,
                                   location_type = "rooftop")

  #add a slight pause so not to overload the call requests
  Sys.sleep(1)
  if(result$status =="OK" ){
    #multiple address can be returned with in gecode request picks the first one
    origAddress$venadd[i] <- result$results$formatted_address[1]
    #use this to collect all addresses:
    #paste(result$results$formatted_address, collapse = "  ")
  }
}

Since the call to google_reverse_geocode returns the address, I just pull the first address from the result saving a call to the internet (performance improvement). Also since the call returns a status, I check for an OK and if exist save the first address.

Hope this helps.

Problems with reverse geocoding loops with latitude longitude co-ordinates using googleway: r gives the same results for different co-ordinates

1 Answers1