Vincenty vs Haversine Distance Calculations

JavaScript performance comparison

Revision 9 of this test case created by

Preparation code


      
      <script>
Benchmark.prototype.setup = function() {
  /** Converts numeric degrees to radians */
  if (typeof(Number.prototype.toRad) === "undefined") {
    Number.prototype.toRad = function() {
      return this * Math.PI / 180;
    }
  }
  
  /**
   * Calculates geodetic distance between two points specified by latitude/longitude using 
   * Vincenty inverse formula for ellipsoids
   *
   * @param   {Number} lat1, lon1: first point in decimal degrees
   * @param   {Number} lat2, lon2: second point in decimal degrees
   * @returns (Number} distance in metres between points
   */
  
  function distVincenty(lat1, lon1, lat2, lon2) {
    var a = 6378137,
        b = 6356752.314245,
        f = 1 / 298.257223563; // WGS-84 ellipsoid params
    var L = (lon2 - lon1).toRad();
    var U1 = Math.atan((1 - f) * Math.tan(lat1.toRad()));
    var U2 = Math.atan((1 - f) * Math.tan(lat2.toRad()));
    var sinU1 = Math.sin(U1),
        cosU1 = Math.cos(U1);
    var sinU2 = Math.sin(U2),
        cosU2 = Math.cos(U2);
  
    var lambda = L,
        lambdaP, iterLimit = 100;
    do {
      var sinLambda = Math.sin(lambda),
          cosLambda = Math.cos(lambda);
      var sinSigma = Math.sqrt((cosU2 * sinLambda) * (cosU2 * sinLambda) + (cosU1 * sinU2 - sinU1 * cosU2 * cosLambda) * (cosU1 * sinU2 - sinU1 * cosU2 * cosLambda));
      if (sinSigma == 0) return 0; // co-incident points
      var cosSigma = sinU1 * sinU2 + cosU1 * cosU2 * cosLambda;
      var sigma = Math.atan2(sinSigma, cosSigma);
      var sinAlpha = cosU1 * cosU2 * sinLambda / sinSigma;
      var cosSqAlpha = 1 - sinAlpha * sinAlpha;
      var cos2SigmaM = cosSigma - 2 * sinU1 * sinU2 / cosSqAlpha;
      if (isNaN(cos2SigmaM)) cos2SigmaM = 0; // equatorial line: cosSqAlpha=0 (§6)
      var C = f / 16 * cosSqAlpha * (4 + f * (4 - 3 * cosSqAlpha));
      lambdaP = lambda;
      lambda = L + (1 - C) * f * sinAlpha * (sigma + C * sinSigma * (cos2SigmaM + C * cosSigma * (-1 + 2 * cos2SigmaM * cos2SigmaM)));
    } while (Math.abs(lambda - lambdaP) > 1e-12 && --iterLimit > 0);
  
    if (iterLimit == 0) return NaN // formula failed to converge
    var uSq = cosSqAlpha * (a * a - b * b) / (b * b);
    var A = 1 + uSq / 16384 * (4096 + uSq * (-768 + uSq * (320 - 175 * uSq)));
    var B = uSq / 1024 * (256 + uSq * (-128 + uSq * (74 - 47 * uSq)));
    var deltaSigma = B * sinSigma * (cos2SigmaM + B / 4 * (cosSigma * (-1 + 2 * cos2SigmaM * cos2SigmaM) - B / 6 * cos2SigmaM * (-3 + 4 * sinSigma * sinSigma) * (-3 + 4 * cos2SigmaM * cos2SigmaM)));
    var s = b * A * (sigma - deltaSigma);
  
    s = s.toFixed(3); // round to 1mm precision
    return s;
  }
  
  // Distance in kilometers between two points using the Haversine algo.
  function haversine(lat1, lon1, lat2, lon2) {
    var R = 6371;
    var dLat = (lat2 - lat1).toRad();
    var dLong = (lon2 - lon1).toRad();
  
    var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) + Math.cos(lat1.toRad()) * Math.cos(lat2.toRad()) * Math.sin(dLong / 2) * Math.sin(dLong / 2);
    var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
    var d = R * c;
  
    return Math.round(d);
  }

};
</script>

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Testing in CCBot 2.0.0 / Other 0.0.0
Test Ops/sec
Vincenty formula
distVincenty(0, 0, 0.5, 179.5);
pending…
Haversine formula
haversine(0, 0, 0.5, 179.5);
pending…

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