Json Data to latitude longitude list

Location-Finder.js

var data = {"merchants":[{"storeList":[{"address":"Unit R01 Paddington Station London W2 1HB","name":"Paddington Station","longitude":"-0.177476","latitude":"51.517596"},{"address":"Unit 53 Broadgate Link (opposite Boots) Liverpool Street Station London EC2M 7PY","name":"Liverpool street","longitude":"-0.081423","latitude":"51.519233"},{"address":"Unit 61 Victoria Station (next to M&S) London SW1V 1JT","name":"Victoria Station","longitude":"-0.143641","latitude":"51.494709"},{"address":"281 Wimbledon Park Road Southfields London SW19 6NW","name":"Wimbledon Park Road","longitude":"-0.207318","latitude":"51.44379"},{"address":"Wimbledon Station Wimbledon SW19 7NL","name":"Wimbledon Station","longitude":"-0.206437","latitude":"51.421571"},{"address":"Unit 1 The Vaults London Bridge Station SE1 9SP","name":"London Bridge Station","longitude":"-0.085975","latitude":"51.504856"},{"address":"Barry House 20-22 Worple Road Wimbledon SW19 4DH","name":"Barry House","longitude":"-0.209519","latitude":"51.420975"},{"address":"Raynes Park Station Approach Road SW20 0JY","name":"Raynes Park Station","longitude":"-0.230244","latitude":"51.408756"}]}]};
var merchants = data.merchants;

var locations = "";
for (i=0; i< merchants.length; i++) {
  if(merchants[i].storeList != undefined) {
    stores = merchants[i].storeList;
    for(j=0; j< stores.length; j++) {
      locations += stores[j].latitude + "," + stores[j].longitude + "\n";
    }
  }
}

console.log(locations);
// Copy the output on this app: http://www.darrinward.com/lat-long/?id=2489595