haversine.js

//Crazy Haversine formula for getting locations within 25 miles of searched location.
//Don't touch this or it will explode!

function hvs1(results, Rga){
	var R = 6371; // Radius of the earth in km
	var dLat = (results[0].geometry.location.b - Rga.FoodBankData[0].Latitude).toRad();  // Javascript functions in radians
	var dLon = (results[0].geometry.location.c - Rga.FoodBankData[0].Longitude).toRad();
	var a = Math.sin(dLat / 2) * Math.sin(dLat / 2) +
			Math.cos(Rga.FoodBankData[0].Latitude.toRad()) * Math.cos(results[0].geometry.location.b.toRad()) *
			Math.sin(dLon / 2) * Math.sin(dLon / 2);
	var c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
	var d = R * c; // Distance in km
	return d;
}

function hvs2(latA, longA, latB, longB){
	var dLat = (latA - latB).toRad(); 
	var dLon = (longA - longB).toRad();
	var dLatDiv2 = dLat / 2;
	var dLonDiv2 = dLon / 2;
	var latBRad = latB.toRad();
	var latBRadCos = Math.cos(latBRad);
	var dLatDiv2Sin = Math.sin(dLatDiv2);
	var dLonDiv2Sin = Math.sin(dLonDiv2);
	var a = dLatDiv2Sin * dLatDiv2Sin + latBRadCos * latBRadCos * dLonDiv2Sin * dLonDiv2Sin;
	return 6371 * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a));
}

function hvs3(latA, longA, latB, longB){
	var a = Math.sin((latA - latB).toRad()/ 2) * Math.sin((latA - latB).toRad() / 2) +
			Math.cos(latB.toRad()) * Math.cos(latB.toRad()) *
			Math.sin((longA - longB).toRad() / 2) * Math.sin((longA - longB).toRad() / 2);
	var d = 6371 * 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a)); // 6371 Radius of the earth in km
	return d;
}

if (typeof (Number.prototype.toRad) === "undefined") {
    Number.prototype.toRad = function() {
        return this * 3.14 / 180;
    }
}


function bench(methodName, param1, param2, param3, param4){
	var start = new Date();
	var i = 0;
	for(i = 0; i < 40000; i++){
		methodName(param1, param2, param3, param4);
	}
	var end = new Date();
	console.log(end.getTime() - start.getTime());
}

var results = [
	{ 
		geometry: {
			location: { b: 10, c: 10 }
		}
	}
];

var Rga = {
	FoodBankData: [
		{ Latitude: 20, Longitude: 20 }
	]
};

bench( hvs1, results, Rga );
bench( hvs2, 20, 20, 10, 10 );
bench( hvs3, 20, 20, 10, 10 );