numerator -> Integer
分子を返します。
例 Rational(7).numerator # => 7 Rational(7, 1).numerator # => 7 Rational(9, -4).numerator # => -9 Rational(-2, -10).numerator # => 1
Rational(7).numerator # => 7 Rational(7, 1).numerator # => 7 Rational(9, -4).numerator # => -9 Rational(-2, -10).numerator # => 1
[SEE_ALSO] Rational#denominator