Actually had trouble using `printf` btw, as in:

```
scala> System.out.printf("%2.2f", 3.0)
<console>:8: error: overloaded method value printf with alternatives:
  (x$1: java.util.Locale,x$2: String,x$3: Object*)java.io.PrintStream <and>
  (x$1: String,x$2: Object*)java.io.PrintStream
 cannot be applied to (String, Double)
```