Data.Ratio

base-4.9.0.0: Basic libraries

Copyright | (c) The University of Glasgow 2001
License | BSD-style (see the file libraries/base/LICENSE)
Maintainer | libraries@haskell.org
Stability | stable
Portability | portable
Safe Haskell | Safe
Language | Haskell2010

Data.Ratio

Description

Standard functions on rational numbers

Synopsis

- data Ratio a
- type Rational = Ratio Integer
- (%) :: Integral a => a -> a -> Ratio a
- numerator :: Ratio a -> a
- denominator :: Ratio a -> a
- approxRational :: RealFrac a => a -> a -> Rational

# Documentation

data Ratio a Source

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

Instances

Integral a => Enum (Ratio a) |
Methods succ :: Ratio a -> Ratio a Source pred :: Ratio a -> Ratio a Source toEnum :: Int -> Ratio a Source fromEnum :: Ratio a -> Int Source enumFrom :: Ratio a -> [Ratio a] Source enumFromThen :: Ratio a -> Ratio a -> [Ratio a] Source enumFromTo :: Ratio a -> Ratio a -> [Ratio a] Source enumFromThenTo :: Ratio a -> Ratio a -> Ratio a -> [Ratio a] Source
Eq a => Eq (Ratio a) |
Methods (==) :: Ratio a -> Ratio a -> Bool Source (/=) :: Ratio a -> Ratio a -> Bool Source
Integral a => Fractional (Ratio a) |
Methods (/) :: Ratio a -> Ratio a -> Ratio a Source recip :: Ratio a -> Ratio a Source fromRational :: Rational -> Ratio a Source
(Data a, Integral a) => Data (Ratio a) |
Methods gfoldl :: (forall d b. Data d => c (d -> b) -> d -> c b) -> (forall g. g -> c g) -> Ratio a -> c (Ratio a) Source gunfold :: (forall b r. Data b => c (b -> r) -> c r) -> (forall r. r -> c r) -> Constr -> c (Ratio a) Source toConstr :: Ratio a -> Constr Source dataTypeOf :: Ratio a -> DataType Source dataCast1 :: Typeable (TYPE Lifted -> TYPE Lifted) t => (forall d. Data d => c (t d)) -> Maybe (c (Ratio a)) Source dataCast2 :: Typeable (TYPE Lifted -> TYPE Lifted -> TYPE Lifted) t => (forall d e. (Data d, Data e) => c (t d e)) -> Maybe (c (Ratio a)) Source gmapT :: (forall b. Data b => b -> b) -> Ratio a -> Ratio a Source gmapQl :: (r -> r' -> r) -> r -> (forall d. Data d => d -> r') -> Ratio a -> r Source gmapQr :: (r' -> r -> r) -> r -> (forall d. Data d => d -> r') -> Ratio a -> r Source gmapQ :: (forall d. Data d => d -> u) -> Ratio a -> [u] Source gmapQi :: Int -> (forall d. Data d => d -> u) -> Ratio a -> u Source gmapM :: Monad m => (forall d. Data d => d -> m d) -> Ratio a -> m (Ratio a) Source gmapMp :: MonadPlus m => (forall d. Data d => d -> m d) -> Ratio a -> m (Ratio a) Source gmapMo :: MonadPlus m => (forall d. Data d => d -> m d) -> Ratio a -> m (Ratio a) Source
Integral a => Num (Ratio a) |
Methods (+) :: Ratio a -> Ratio a -> Ratio a Source (-) :: Ratio a -> Ratio a -> Ratio a Source (*) :: Ratio a -> Ratio a -> Ratio a Source negate :: Ratio a -> Ratio a Source abs :: Ratio a -> Ratio a Source signum :: Ratio a -> Ratio a Source fromInteger :: Integer -> Ratio a Source
Integral a => Ord (Ratio a) |
Methods compare :: Ratio a -> Ratio a -> Ordering Source (<) :: Ratio a -> Ratio a -> Bool Source (<=) :: Ratio a -> Ratio a -> Bool Source (>) :: Ratio a -> Ratio a -> Bool Source (>=) :: Ratio a -> Ratio a -> Bool Source max :: Ratio a -> Ratio a -> Ratio a Source min :: Ratio a -> Ratio a -> Ratio a Source
(Integral a, Read a) => Read (Ratio a) |
Methods readsPrec :: Int -> ReadS (Ratio a) Source readList :: ReadS [Ratio a] Source readPrec :: ReadPrec (Ratio a) Source readListPrec :: ReadPrec [Ratio a] Source
Integral a => Real (Ratio a) |
Methods toRational :: Ratio a -> Rational Source
Integral a => RealFrac (Ratio a) |
Methods properFraction :: Integral b => Ratio a -> (b, Ratio a) Source truncate :: Integral b => Ratio a -> b Source round :: Integral b => Ratio a -> b Source ceiling :: Integral b => Ratio a -> b Source floor :: Integral b => Ratio a -> b Source
Show a => Show (Ratio a) |
Methods showsPrec :: Int -> Ratio a -> ShowS Source show :: Ratio a -> String Source showList :: [Ratio a] -> ShowS Source
(Storable a, Integral a) => Storable (Ratio a) |
Methods sizeOf :: Ratio a -> Int Source alignment :: Ratio a -> Int Source peekElemOff :: Ptr (Ratio a) -> Int -> IO (Ratio a) Source pokeElemOff :: Ptr (Ratio a) -> Int -> Ratio a -> IO () Source peekByteOff :: Ptr b -> Int -> IO (Ratio a) Source pokeByteOff :: Ptr b -> Int -> Ratio a -> IO () Source peek :: Ptr (Ratio a) -> IO (Ratio a) Source poke :: Ptr (Ratio a) -> Ratio a -> IO () Source

type Rational = Ratio Integer Source

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 Source

Forms the ratio of two integral numbers.

numerator :: Ratio a -> a Source

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

denominator :: Ratio a -> a Source

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 Source

`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.