PHP show only significant (non-zero) decimals

Question

In PHP (using built-in functions) I\'d like to convert/format a number with decimal, so that only the non-zero decimals show. However, another requirement of mine is that if

Answer 1

 %s\n",
            $number,
            (float) $number == (int) $number ? number_format($number, 1) : (float) $number
        );
    }
?>

Output:

9.000 -> 9.0
9.100 -> 9.1
9.120 -> 9.12
9.123 -> 9.123