# Digits

Returns the string `$value`, removing all but digits.

## Supported options for Zend_Filter_Digits

There are no additional options for `Zend_Filter_Digits`.

## Basic usage

A basic example of usage is below:

    $filter = new Zend_Filter_Digits();

    print $filter->filter('October 2009');

This returns "2009".

    $filter = new Zend_Filter_Digits();

    print $filter->filter('HTML 5 for Dummies');

This returns "5".