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GHC.Real
Copyright | (c) The University of Glasgow 1994-2002 |
---|---|
License | see libraries/base/LICENSE |
Maintainer | cvs-ghc@haskell.org |
Stability | internal |
Portability | non-portable (GHC Extensions) |
Safe Haskell | Trustworthy |
Language | Haskell2010 |
divZeroError :: a Source
ratioZeroDenominatorError :: a Source
overflowError :: a Source
underflowError :: a Source
Rational numbers, with numerator and denominator of some Integral
type.
Note that Ratio
's instances inherit the deficiencies from the type parameter's. For example, Ratio Natural
's Num
instance has similar problems to Natural
's.
Constructors
!a :% !a |
Instances
(Data a, Integral a) => Data (Ratio a) Source | Since: base-4.0.0.0 |
Defined in Data.Data Methodsgfoldl :: (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 t => (forall d. Data d => c (t d)) -> Maybe (c (Ratio a)) Source dataCast2 :: Typeable 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 :: forall r r'. (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 |
|
(Storable a, Integral a) => Storable (Ratio a) Source | Since: base-4.8.0.0 |
Defined in Foreign.Storable MethodssizeOf :: 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 |
|
Integral a => Enum (Ratio a) Source | Since: base-2.0.1 |
Defined in GHC.Real Methodssucc :: 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 |
|
Integral a => Num (Ratio a) Source | Since: base-2.0.1 |
Defined in GHC.Real |
|
(Integral a, Read a) => Read (Ratio a) Source | Since: base-2.1 |
Integral a => Fractional (Ratio a) Source | Since: base-2.0.1 |
Integral a => Real (Ratio a) Source | Since: base-2.0.1 |
Defined in GHC.Real MethodstoRational :: Ratio a -> Rational Source |
|
Integral a => RealFrac (Ratio a) Source | Since: base-2.0.1 |
Show a => Show (Ratio a) Source | Since: base-2.0.1 |
Eq a => Eq (Ratio a) Source | Since: base-2.1 |
Integral a => Ord (Ratio a) Source | Since: base-2.0.1 |
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.
ratioPrec1 :: Int Source
(%) :: 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.
reduce :: Integral a => a -> a -> Ratio a Source
reduce
is a subsidiary function used only in this module. It normalises a ratio by dividing both numerator and denominator by their greatest common divisor.
class (Num a, Ord a) => Real a where Source
Methods
toRational :: a -> Rational Source
the rational equivalent of its real argument with full precision
Instances
class (Real a, Enum a) => Integral a where Source
Integral numbers, supporting integer division.
The Haskell Report defines no laws for Integral
. However, Integral
instances are customarily expected to define a Euclidean domain and have the following properties for the div
/mod
and quot
/rem
pairs, given suitable Euclidean functions f
and g
:
x
=y * quot x y + rem x y
withrem x y
=fromInteger 0
org (rem x y)
<g y
x
=y * div x y + mod x y
withmod x y
=fromInteger 0
orf (mod x y)
<f y
An example of a suitable Euclidean function, for Integer
's instance, is abs
.
Methods
quot :: a -> a -> a infixl 7 Source
integer division truncated toward zero
WARNING: This function is partial (because it throws when 0 is passed as the divisor) for all the integer types in base
.
rem :: a -> a -> a infixl 7 Source
integer remainder, satisfying
(x `quot` y)*y + (x `rem` y) == x
WARNING: This function is partial (because it throws when 0 is passed as the divisor) for all the integer types in base
.
div :: a -> a -> a infixl 7 Source
integer division truncated toward negative infinity
WARNING: This function is partial (because it throws when 0 is passed as the divisor) for all the integer types in base
.
mod :: a -> a -> a infixl 7 Source
integer modulus, satisfying
(x `div` y)*y + (x `mod` y) == x
WARNING: This function is partial (because it throws when 0 is passed as the divisor) for all the integer types in base
.
quotRem :: a -> a -> (a, a) Source
WARNING: This function is partial (because it throws when 0 is passed as the divisor) for all the integer types in base
.
divMod :: a -> a -> (a, a) Source
WARNING: This function is partial (because it throws when 0 is passed as the divisor) for all the integer types in base
.
toInteger :: a -> Integer Source
conversion to Integer
Instances
class Num a => Fractional a where Source
Fractional numbers, supporting real division.
The Haskell Report defines no laws for Fractional
. However, (+)
and (*)
are customarily expected to define a division ring and have the following properties:
-
recip
gives the multiplicative inverse x * recip x
=recip x * x
=fromInteger 1
Note that it isn't customarily expected that a type instance of Fractional
implement a field. However, all instances in base
do.
Minimal complete definition
fromRational, (recip | (/))
Methods
(/) :: a -> a -> a infixl 7 Source
Fractional division.
Reciprocal fraction.
fromRational :: Rational -> a Source
Conversion from a Rational
(that is Ratio Integer
). A floating literal stands for an application of fromRational
to a value of type Rational
, so such literals have type (Fractional a) => a
.
Instances
Fractional CDouble Source | |
Fractional CFloat Source | |
Fractional Double Source | Note that due to the presence of Since: base-2.1 |
Fractional Float Source | Note that due to the presence of Since: base-2.1 |
RealFloat a => Fractional (Complex a) Source | Since: base-2.1 |
Fractional a => Fractional (Identity a) Source | Since: base-4.9.0.0 |
Fractional a => Fractional (Down a) Source | Since: base-4.14.0.0 |
Integral a => Fractional (Ratio a) Source | Since: base-2.0.1 |
HasResolution a => Fractional (Fixed a) Source | Since: base-2.1 |
Fractional a => Fractional (Op a b) Source | |
Fractional a => Fractional (Const a b) Source | Since: base-4.9.0.0 |
class (Real a, Fractional a) => RealFrac a where Source
Extracting components of fractions.
Minimal complete definition
Methods
properFraction :: Integral b => a -> (b, a) Source
The function properFraction
takes a real fractional number x
and returns a pair (n,f)
such that x = n+f
, and:
n
is an integral number with the same sign asx
; andf
is a fraction with the same type and sign asx
, and with absolute value less than1
.
The default definitions of the ceiling
, floor
, truncate
and round
functions are in terms of properFraction
.
truncate :: Integral b => a -> b Source
truncate x
returns the integer nearest x
between zero and x
round :: Integral b => a -> b Source
round x
returns the nearest integer to x
; the even integer if x
is equidistant between two integers
ceiling :: Integral b => a -> b Source
ceiling x
returns the least integer not less than x
floor :: Integral b => a -> b Source
floor x
returns the greatest integer not greater than x
Instances
RealFrac CDouble Source | |
RealFrac CFloat Source | |
RealFrac Double Source | Since: base-2.1 |
RealFrac Float Source | Since: base-2.1 |
RealFrac a => RealFrac (Identity a) Source | Since: base-4.9.0.0 |
RealFrac a => RealFrac (Down a) Source | Since: base-4.14.0.0 |
Integral a => RealFrac (Ratio a) Source | Since: base-2.0.1 |
HasResolution a => RealFrac (Fixed a) Source | Since: base-2.1 |
RealFrac a => RealFrac (Const a b) Source | Since: base-4.9.0.0 |
numericEnumFrom :: Fractional a => a -> [a] Source
numericEnumFromThen :: Fractional a => a -> a -> [a] Source
numericEnumFromTo :: (Ord a, Fractional a) => a -> a -> [a] Source
numericEnumFromThenTo :: (Ord a, Fractional a) => a -> a -> a -> [a] Source
fromIntegral :: (Integral a, Num b) => a -> b Source
General coercion from Integral
types.
WARNING: This function performs silent truncation if the result type is not at least as big as the argument's type.
realToFrac :: (Real a, Fractional b) => a -> b Source
General coercion to Fractional
types.
WARNING: This function goes through the Rational
type, which does not have values for NaN
for example. This means it does not round-trip.
For Double
it also behaves differently with or without -O0:
Prelude> realToFrac nan -- With -O0
-Infinity
Prelude> realToFrac nan
NaN
Arguments
Converts a possibly-negative Real
value to a string.
even :: Integral a => a -> Bool Source
odd :: Integral a => a -> Bool Source
(^) :: (Num a, Integral b) => a -> b -> a infixr 8 Source
raise a number to a non-negative integral power
(^^) :: (Fractional a, Integral b) => a -> b -> a infixr 8 Source
raise a number to an integral power
(^%^) :: Integral a => Rational -> a -> Rational Source
(^^%^^) :: Integral a => Rational -> a -> Rational Source
gcd :: Integral a => a -> a -> a Source
gcd x y
is the non-negative factor of both x
and y
of which every common factor of x
and y
is also a factor; for example gcd 4 2 = 2
, gcd (-4) 6 = 2
, gcd 0 4
= 4
. gcd 0 0
= 0
. (That is, the common divisor that is "greatest" in the divisibility preordering.)
Note: Since for signed fixed-width integer types, abs minBound < 0
, the result may be negative if one of the arguments is minBound
(and necessarily is if the other is 0
or minBound
) for such types.
lcm :: Integral a => a -> a -> a Source
lcm x y
is the smallest positive integer that both x
and y
divide.
integralEnumFrom :: (Integral a, Bounded a) => a -> [a] Source
integralEnumFromThen :: (Integral a, Bounded a) => a -> a -> [a] Source
integralEnumFromTo :: Integral a => a -> a -> [a] Source
integralEnumFromThenTo :: Integral a => a -> a -> a -> [a] Source
data FractionalExponentBase Source
Instances
Show FractionalExponentBase Source | |
Defined in GHC.Real MethodsshowsPrec :: Int -> FractionalExponentBase -> ShowS Source show :: FractionalExponentBase -> String Source showList :: [FractionalExponentBase] -> ShowS Source |
mkRationalBase2 :: Rational -> Integer -> Rational Source
mkRationalBase10 :: Rational -> Integer -> Rational Source
mkRationalWithExponentBase :: Rational -> Integer -> FractionalExponentBase -> Rational Source
© The University of Glasgow and others
Licensed under a BSD-style license (see top of the page).
https://downloads.haskell.org/~ghc/9.4.2/docs/libraries/base-4.17.0.0/GHC-Real.html