PHP convert decimal into fraction and back?

Question

I want the user to be able to type in a fraction like:

 1/2
 2 1/4
 3

And convert it into its corresponding decimal, to be saved in MySQL,

Answer 1

Just adding a bit more logic to Derek's accepted answer - check for "division by zero" and whole number input check.

function fractionToDec($input) {
    if (strpos($input, '/') === FALSE) {
        $result = $input;
    } else {
        $fraction = array('whole' => 0);
        preg_match('/^((?P\d+)(?=\s))?(\s*)?(?P\d+)\/(?P\d+)$/', $input, $fraction);
        $result = $fraction['whole'];

        if ($fraction['denominator'] > 0)
            $result += $fraction['numerator'] / $fraction['denominator'];
    }

    return $result;
}