CFLib.org – Common Function Library Project

Description:
Calculates distance between Latitude/Longitude points using haversine formula : http://www.movable-type.co.uk/scripts/latlong.html

Return Values:
Returns numeric distance between the two points. Units varies, default is miles.

Example:

#getDistance(1, 1, 2, 2)#

Parameters:

Full UDF Source:

/**
 * Calculates distance between Latitude/Longitude points using haversine formula.
 * 
 * @param lat1      latitude of first point (Required)
 * @param lon1      longitude of first point (Required)
 * @param lat2      latitude of second point (Required)
 * @param lon2      longitude of second point (Required)
 * @param units      Units for return value. Default is miles. (Optional)
 * @return Returns numeric distance between the two points. Units varies, default is miles. 
 * @author Henry Ho (henryho167@gmail.com) 
 * @version 0, January 8, 2013 
 */
function getDistance(lat1, lon1, lat2, lon2, units = 'miles')
{
    // earth's radius. Default is miles.
    var radius = 3959;
    if (arguments.units EQ 'kilometers' )
        radius = 6371;
    else if (arguments.units EQ 'feet')
        radius = 20903520;
    
    var toRad = pi() / 180;
    var dLat = (lat2-lat1) * toRad;
    var dLon = (lon2-lon1) * toRad; 
    var a = sin(dLat/2)^2 + cos(lat1 * toRad) * cos(lat2 * toRad) * sin(dLon/2)^2; 
    var c = 2 * createObject("java","java.lang.Math").atan2(sqr(a), sqr(1-a));
    
    return radius * c;
}