Ratio

Synopsis

# Documentation

data Ratio a :: * -> *

Rational numbers, with numerator and denominator of some `Integral` type.

Instances

 Integral a => Enum (Ratio a) Eq a => Eq (Ratio a) Integral a => Fractional (Ratio a) Integral a => Num (Ratio a) Integral a => Ord (Ratio a) (Integral a, Read a) => Read (Ratio a) Integral a => Real (Ratio a) Integral a => RealFrac (Ratio a) (Integral a, Show a) => Show (Ratio a)

type Rational = Ratio Integer

Arbitrary-precision rational numbers, represented as a ratio of two `Integer` values. A rational number may be constructed using the `%` operator.

(%) :: Integral a => a -> a -> Ratio a infixl 7

Forms the ratio of two integral numbers.

numerator :: Integral a => Ratio a -> a

Extract the numerator of the ratio in reduced form: the numerator and denominator have no common factor and the denominator is positive.

denominator :: Integral a => Ratio a -> a

Extract the denominator of the ratio in reduced form: the numerator and denominator have no common factor and the denominator is positive.

approxRational :: RealFrac a => a -> a -> Rational

`approxRational`, applied to two real fractional numbers `x` and `epsilon`, returns the simplest rational number within `epsilon` of `x`. A rational number `y` is said to be simpler than another `y'` if

• `abs (numerator y) <= abs (numerator y')`, and
• `denominator y <= denominator y'`.

Any real interval contains a unique simplest rational; in particular, note that `0/1` is the simplest rational of all.