Code: Select all
/************************************************
*************************************************
** this function will return a **
** $min_lat, $max_lat, $min_lon, $max_lon **
** for use of calculating which lattitude and **
** longitudes are in a given range of a **
** specified $lat & $lon **
*************************************************
************************************************/
function getPoints($zip,$range){
// firstly get lat & long for given zip code
// this part is OK - returns correct data
// $latlon is an associative array
if(!$latlon = $this->getZipData($zip)){
return false;
}
// declare variables for easier usage
$lat = $latlon['lat'];
$lon = $latlon['long'];
// calculate ranges
$lat_range = $range/69.172;
$lon_range = abs($range/(cos($lat) * 69.172));
$min_lat = $lat - $lat_range;
$max_lat = $lat + $lat_range;
$min_lon = $lon - $lon_range;
$max_lon = $lon + $lon_range;
return array($min_lat,$max_lat,$min_lon,$max_lon);
}