php正则如何替换数字

$str = ereg_replace(‘[^0-9]‘,”,$str);和
$str = preg_replace( ‘/[^＼d]/ ‘, ‘ ‘,$str);

function findNum($str=''){
$str=trim($str);
if(empty($str)){return '';}
$reg='/(＼d{3}(＼.＼d+)?)/is';//匹配数字的正则表达式
preg_match_all($reg,$str,$result);
if(is_array($result)&&!empty($result)&&!empty($result[1])&&!empty($result[1][0])){
return $result[1][0];
}
return '';
}

 $regexp = '/(＼d+)＼.(＼d+)/is';
$total = "42.234 EUR 53.218 AUD CAD97.164 311.151 MYR 125.042 NZD GBP84.270 SGD60.227 USD134.400";
preg_match_all('/(＼d+)＼.(＼d+)/is', $total, $arr);
var_export($arr);
 ?>