$re = '/(\+|\-)?((180)|(1[0-7]\d|[0]?\d\d|[0]?\d))\s*°\s*(([1-5]\d|[0]?\d)(\.\d+)?\s*\')\s*(w|W|e|E)?/';
$str = '179° 36.000\'';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php