Here is a very handy function, which calculate the distance from a point A to a point B, using latitudes and longitudes. The function can return the distance in miles, kilometers, or nautical miles.

<pre>function calculate_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;
      }
}

</pre>

Usage

Using the function is pretty simple: All you need to do is to call it. Parameters are: from latitude, fromlongitude, to latitude, to longitude and unit, which can be m for miles, k for kilometers, and n for nautical miles

//Miles echo calculate_distance(32.9697, -96.80322, 29.46786, -98.53506, “m”) . ” miles”;

//Kilometers echo calculate_distance(32.9697, -96.80322, 29.46786, -98.53506, “k”) . ” kilometers”;

//Nautical miles echo calculate_distance(32.9697, -96.80322, 29.46786, -98.53506, “n”) . ” nautical miles”;

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Karthikeyan KPHPdistances,php
Here is a very handy function, which calculate the distance from a point A to a point B, using latitudes and longitudes. The function can return the distance in miles, kilometers, or nautical miles.UsageUsing the function is pretty simple: All you need to do is to call it. Parameters...