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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

            
              <div style='font-family: sans-serif; text-align:center; font-size:1em;'>
  <input id="btn" type="button" value="What is the nearest Belgian railway station? (we wil not send your location to the server)" onClick="javascript:getClosestStation()" style="width: 100%;height: 50px;border: 2px;font-size:1em;"/>
  <div id="result"></div>
</div>
            
          
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              // First gets geolocation from the browser (end user may have to allow browser to access geolocation).
// Then gets stations list from iRail project and sorts this by distance. It then takes the top element to show to the end user.
function getClosestStation() {
  console.log("getting geolocation");
  navigator.geolocation.getCurrentPosition(function(position) {
    console.log("got geolocation");
    fetch("https://api.irail.be/stations/?format=json").then(function(body) {
      return body.json();
    }).then(function(doc) {
      var stations = doc.station.sort(function(a, b) {
        return haversineDistance({
          latitude: parseFloat(a.locationY),
          longitude: parseFloat(a.locationX)
        }, position.coords) - haversineDistance({
          latitude: parseFloat(b.locationY),
          longitude: parseFloat(b.locationX)
        }, position.coords);
      }, function (e) {
        console.error(e);
        throw "Does not";
      });
      var str = "<p>The closest station to your current location is <em>" + stations[0].name + "</em>.</p><small>Curious what the second closest station is? We already know. Here’s the top 5: ";
      str+= stations[0].name;
      for (var i = 1; i < 5; i++) {
        str+= ", " + stations[i].name;
      }
      str+="</small>";
      document.getElementById("result").innerHTML  = str;
    }).catch(function(err) {
      console.log("error: " + err);
      document.getElementById("result").innerHTML  = "Could not retrieve iRail stations list from your browser";
    });
  }, (error) => {
    console.error(error.message); 
   document.getElementById("result").innerHTML  = "Could not get your current location from your browser I’m afraid. (did you allow me to get your location?)";

  }
  );
}

//Calculates the distance between 2 points on a globe
function haversineDistance(P1, P2) {
  Number.prototype.toRad = function() {
    return this * Math.PI / 180;
  }
  var lat2 = P2.latitude;
  var lon2 = P2.longitude;
  var lat1 = P1.latitude;
  var lon1 = P1.longitude;
  var R = 6371; // km 
  var x1 = lat2 - lat1;
  var dLat = x1.toRad();
  var x2 = lon2 - lon1;
  var dLon = x2.toRad();
  var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) + Math.cos(lat1.toRad()) * Math.cos(lat2.toRad()) *
    Math.sin(dLon / 2) * Math.sin(dLon / 2);
  var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
  return R * c;
}

            
          
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