Round to a given PHP

[fbio]

I need to round up the numbers to the assignment manually, for example:

131 -> 0
385 -> 500
831 -> 1000
749 -> 500

How can that be done?

[shizuka]

for a fixed number of points, something like this will happen.

$points = [0,500,1000];    
$data   = [131,385,831,749];
$finder = function($v) use ($points) {

$min = PHP_INT_MAX;

$res = null;
        foreach($points as $idx => $p){
            if($min > abs($p - $v)){
                $min = abs($p-$v);
                $res = $p;
            }
        }
        return $res;
            
      };

foreach($data as $v){

echo "$v - {$finder($v)}\n";

}