Sanitizing Numbers

I'm trying to sanitize some numeric data that's coming to us from another system which I have no control over where all fields are character fields with no formatting from the end user so data is a mishmash of clean and mixed types of dirty. I know I can use intval and floatval to sanitize if the numeric data is at the front of the string but what about when it's not? For example, Jersey Number = #45 or Dues = $1,234.56.... I see in the comments at php.net for floatval a lot of very complex solutions... am I missing something about the following that wouldn't cover me? <?php $output = floatval(ereg_replace("[^-0-9\.]","",$input)); ?> I'm willing to assuming only US formatted numbers... and knowing that if they put in 45/46 for jersey it would come out 4546 (but I might put in additional code for that specific case on that specific field...). I'm also looking for something that I can generically apply to any numeric field. Thanks for your collective guidance. Matt