title: how do I read a Json File and store some data in an array and then later after reading the file access it?
body: <p>As show in the code below, I'am trying to read a Json File and push some values from the json file into an array, if the array is accessed within the function, the value is correctly stored</p>
  
  <p>But when the callback function ends, the array is empty
  Why does the array not contain the values pushed?</p>
  
  <pre><code>var latArray = new Array();
  var longArray = new Array();
  var getLatLong = d3.json("./SRC/ratp_2013.json", function (error, data){
  
  
  
          for(i in data.stops)
          {
              longArray.push(data.stops[i].longitude);
              latArray.push(data.stops[i].latitude);
          }
  
          console.log(longArray); //Prints the Array of latitudes
          console.log(latArray);  //Prints the Array of longitudes
  });
  console.log(longArray); //Prints an empty array.
  console.log(latArray);  //Prints an empty array.
  </code></pre>