$re = '/-?\b\d+(?:\.\d+)?(?:\|\-?\d+(?:\.\d+)?){3}\b/m';
$str = '13|5|-1|3 or 5|5|0|3 or 13|4|1.5|1
The string may also contain additional numbers and words; a full example looks like so:
SOME STRING CONTENT 13|5|-1|3 MORE 1.6 CONTENT HERE';
preg_match_all($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