Run results for: Haversine

Test name	Executions per second
✓ Distance3	92 Ops/sec
Distance4	91 Ops/sec
Distance5	90 Ops/sec
Distance2	77 Ops/sec
Distance1	72 Ops/sec
Script Preparation code:
  var TO_RAD = Math.PI / 180;
  
  function toRad(deg) {
   return deg * TO_RAD;
  }
  
  var coords = new Array();
  
  function randomLat() {
   return Math.random() * 180 - 90;
  }
  
  function randomLong() {
   return Math.random() * 360 - 180;
  }
  
  for (var i = 0; i < 5000; i++) {
   coords.push([randomLat(), randomLong(), randomLat(), randomLong()]);
  }
  
  function compute(coord, f) {
   return f(coord[0], coord[1], coord[2], coord[3]);
  }
  
  function test(f) {
   for (var i = 0; i < coords.length; i++) {
    var coord = coords[i];
    compute(coord, f);
   }
  }
  
  var R = 6371009; // m
  var R2 = 6371009 * 2; // m
  
  function distance1(lat1, lon1, lat2, lon2) {
   var R = 6371009; // m
   var dLat = toRad(lat2 - lat1);
   var dLon = toRad(lon2 - lon1);
  
   var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) + Math.cos(toRad(lat1)) * Math.cos(toRad(lat2)) * Math.sin(dLon / 2) * Math.sin(dLon / 2);
   var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
   return R * c;
  }
  
  function distance2(lat1, lon1, lat2, lon2) {
   var aLat = toRad(lat1);
   var bLat = toRad(lat2);
   var dLat2 = (bLat - aLat) / 2;
   var dLon2 = toRad(lon2 - lon1) / 2;
   var x = Math.sin(dLat2) * Math.sin(dLat2) + Math.cos(aLat) * Math.cos(bLat) * Math.sin(dLon2) * Math.sin(dLon2);
   return R * 2 * Math.atan2(Math.sqrt(x), Math.sqrt(1 - x));
  }
  
  function distance3(lat1, lon1, lat2, lon2) {
   var aLat = toRad(lat1);
   var bLat = toRad(lat2);
   var dLat2 = (bLat - aLat) * 0.5;
   var dLon2 = toRad(lon2 - lon1) * 0.5;
   var sindLat = Math.sin(dLat2);
   var sindLon = Math.sin(dLon2);
   var x = sindLat * sindLat + Math.cos(aLat) * Math.cos(bLat) * sindLon * sindLon;
   return R2 * Math.atan2(Math.sqrt(x), Math.sqrt(1 - x));
  }
  
  function distance4(lat1, lon1, lat2, lon2) {
   var aLat = lat1 * TO_RAD;
   var bLat = lat2 * TO_RAD;
   var dLat2 = (bLat - aLat) * 0.5;
   var dLon2 = (lon2 - lon1) * TO_RAD * 0.5;
   var sindLat = Math.sin(dLat2);
   var sindLon = Math.sin(dLon2);
   var x = sindLat * sindLat + Math.cos(aLat) * Math.cos(bLat) * sindLon * sindLon;
   return R2 * Math.atan2(Math.sqrt(x), Math.sqrt(1 - x));
  }
  
  function distance5(lat1, lon1, lat2, lon2) {
   var aLat = toRad(lat1);
   var bLat = toRad(lat2);
   var dLat2 = (bLat - aLat) * 0.5;
   var dLon2 = toRad(lon2 - lon1) * 0.5;
   var sindLat = Math.sin(dLat2);
   var sindLon = Math.sin(dLon2);
   var x = sindLat * sindLat + Math.cos(aLat) * Math.cos(bLat) * sindLon * sindLon;
   return R2 * Math.asin(Math.sqrt(x));
  }
Distance1

Distance2

Distance3

Distance4

Distance5
