$re = '/^(?:((\d+(?=[^.]+|\.{2,})).)+|(\d\.){2,}).*|[^\d]+$/m';
$str = '1
1.7654
-2.5
2-
2...33
m
2..3
2....233..6
2.2.8
2--5
6-4-9';
preg_match_all($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