The number to round.
The power base to round to. Defaults to 10. Must be greater than 1 (can be fractional, although not recommended).
The accuracy / significant figures to round to. Defaults to 0. Must be greater than 1.
The maximum power to round to. Defaults to 1000. If x > base^max, x is returned.
Function to round a number to the nearest power of a specified base.