kind=defined
names=**
visibility=public

--- **(other)

冪を計算します。

  Rational(3, 4) ** 2              # => Rational(9, 16)
  Rational(3, 4) ** Rational(2, 1) # => 0.5625
  Rational(3, 4) ** 2.0            # => 0.5625

