Finish project. Please read the readme.

Signed-off-by: Rick Hays <rhays@haysgang.com>

classes/geocode.php

@@ -0,0 +1,35 @@
+<?php
+
+	class geocode
+	{
+		/**
+		 * straight_line_distance - Returns Straight Line distance between two sets of (LAT/LONGS)
+		 * @param  real	   $lat1 - Latitude of Location #1
+		 * @param  real	   $lon1 - Longitude of Location #1
+		 * @param  real	   $lat2 - Latitude of Location #2
+		 * @param  real	   $lon2 - Longitude of Location #2
+		 * @param  string  $unit - Unit of measure [DEFAULT = statute miles] ('K'=kilometers, 'N'=nautical miles)
+		 * @return numeric - returns the distance in the desired unit of measure.
+		 */
+		public function straight_line_distance($lat1, $lon1, $lat2, $lon2, $unit='')
+		{
+			$theta = $lon1 - $lon2;
+			$dist = sin(deg2rad($lat1)) * sin(deg2rad($lat2)) +  cos(deg2rad($lat1)) * cos(deg2rad($lat2)) * cos(deg2rad($theta));
+			$dist = acos($dist);
+			$dist = rad2deg($dist);
+			$miles = $dist * 60 * 1.1515;
+			$unit = strtoupper($unit);
+			if ($unit == "K")
+			{
+				return ($miles * 1.609344);
+			}
+			else if ($unit == "N")
+			{
+				return ($miles * 0.8684);
+			}
+			else
+			{
+				return $miles;
+			}
+		}
+	}