preg_replace, negate regex pattern

Question

This is my pattern which i want to negate:

[\+\-][0-9\.]+

These are sample rows:

Stephane Robert (+1.5 Sets)
Stephane Robert (-1.5 Sets)
Philipp Kohlschreiber
Philipp Kohlschreiber (-1.5 Sets)
Philipp Kohlschreiber (+1.5 Sets)
Player Names (n)
Another Player-Player

I want to strip all but the numbers, matching the pattern, i.e. i want only the positive or negative float number.

+1.5
-1.5
-1.5
+1.5

I'm using php and preg_replace.

Thanks!

Answer 1

You can use this. This will also remove other lines which doesn't have the desired value.

(?=.*[+-]\d+\.\d+).*([+-]\d+\.\d+).*|(.*)

Explanation

PHP Code sample

$re = '/(?=.*[+-]\d+\.\d+).*([+-]\d+\.\d+).*|(.*)/m';
    $str = 'Stephane Robert (+1.5 Sets)
    Stephane Robert (-1.5 Sets)
    Philipp Kohlschreiber
    Philipp Kohlschreiber (-1.5 Sets)
    Philipp Kohlschreiber (+1.5 Sets)
    Player Names (n)
    Another Player-Player';
    $subst = '\\1';

    $result = preg_replace($re, $subst, $str);

    echo $result;