Safe Haskell	None
Language	Haskell2010

Haspara.Internal.Quantity

Contents

Orphan instances

Synopsis

newtype Quantity (s :: Nat) = MkQuantity {
- unQuantity :: Decimal RoundHalfEven s Integer
}
quantity :: KnownNat s => Scientific -> Quantity s
quantityAux :: forall s. KnownNat s => Scientific -> Quantity s
quantityLossless :: (KnownNat s, MonadError String m) => Scientific -> m (Quantity s)
roundQuantity :: KnownNat k => Quantity (n + k) -> Quantity n
times :: (KnownNat s, KnownNat k) => Quantity s -> Quantity k -> Quantity s
timesLossless :: (KnownNat s, KnownNat k) => Quantity s -> Quantity k -> Quantity (s + k)
roundScientific :: Int -> Scientific -> Scientific

Documentation

>>> :set -XDataKinds

newtype Quantity (s :: Nat) Source #

Type encoding for common quantity values with given scaling (digits after the decimal point).

>>> 42 :: Quantity 0
42
>>> 42 :: Quantity 1
42.0
>>> 42 :: Quantity 2
42.00
>>> 41 + 1 :: Quantity 2
42.00
>>> 43 - 1 :: Quantity 2
42.00
>>> 2 * 3 * 7 :: Quantity 2
42.00
>>> negate (-42) :: Quantity 2
42.00
>>> abs (-42) :: Quantity 2
42.00
>>> signum (-42) :: Quantity 2
-1.00
>>> fromInteger 42 :: Quantity 2
42.00
>>> quantity 0.415 :: Quantity 2
0.42
>>> quantity 0.425 :: Quantity 2
0.42
>>> quantityLossless 0.42 :: Either String (Quantity 2)
Right 0.42
>>> quantityLossless 0.415 :: Either String (Quantity 2)
Left "Underflow while trying to create quantity: 0.415"

Constructors

MkQuantity
Fields unQuantity :: Decimal RoundHalfEven s Integer

Instances

Instances details

Lift (Quantity s :: Type) Source #	`Lift` instance for `Quantity`.
Instance details Defined in Haspara.Internal.Quantity Methods lift :: Quantity s -> Q Exp # liftTyped :: Quantity s -> Q (TExp (Quantity s)) #
Eq (Quantity s) Source #
Instance details Defined in Haspara.Internal.Quantity Methods (==) :: Quantity s -> Quantity s -> Bool # (/=) :: Quantity s -> Quantity s -> Bool #
KnownNat s => Fractional (Arith (Quantity s)) Source #	Fractional arithmetic over `Quantity` values. `>>>` `import Numeric.Decimal``>>>` `arithM (fromRational 0.42) :: Either SomeException (Quantity 2)`Right 0.42 `>>>` `arithM (fromRational 0.415) :: Either SomeException (Quantity 2)`Left PrecisionLoss (83 % 200) to 2 decimal spaces `>>>` `arithM $ (fromRational 0.84) / (fromRational 2) :: Either SomeException (Quantity 2)`Right 0.42 `>>>` `arithM $ (fromRational 0.42) / (fromRational 0) :: Either SomeException (Quantity 2)`Left divide by zero `>>>` `let a = 84 :: Quantity 2``>>>` `let b = 2 :: Quantity 2``>>>` `let c = 0 :: Quantity 2``>>>` `arithM (Arith a / Arith b) :: Either SomeException (Quantity 2)`Right 42.00 `>>>` `arithM (Arith a / Arith b / Arith c) :: Either SomeException (Quantity 2)`Left divide by zero
Instance details Defined in Haspara.Internal.Quantity Methods (/) :: Arith (Quantity s) -> Arith (Quantity s) -> Arith (Quantity s) # recip :: Arith (Quantity s) -> Arith (Quantity s) # fromRational :: Rational -> Arith (Quantity s) #
KnownNat s => Num (Arith (Quantity s)) Source #	Numeric arithmetic over `Quantity` values. `>>>` `import Numeric.Decimal``>>>` `let a = Arith (quantity 10) + Arith (quantity 32) :: Arith (Quantity 2)``>>>` `arithMaybe a`Just 42.00 `>>>` `arithM (41 + 1) :: Either SomeException (Quantity 2)`Right 42.00 `>>>` `arithM (43 - 1) :: Either SomeException (Quantity 2)`Right 42.00 `>>>` *`arithM (2 3 * 7) :: Either SomeException (Quantity 2)`Right 42.00 `>>>` `arithM (signum 42) :: Either SomeException (Quantity 2)`Right 1.00 `>>>` `arithM (signum (-42)) :: Either SomeException (Quantity 2)`Right -1.00 `>>>` `arithM (abs 42) :: Either SomeException (Quantity 2)`Right 42.00 `>>>` `arithM (abs (-42)) :: Either SomeException (Quantity 2)`Right 42.00 `>>>` `arithM (fromInteger 42) :: Either SomeException (Quantity 2)`**Right 42.00
Instance details Defined in Haspara.Internal.Quantity Methods (+) :: Arith (Quantity s) -> Arith (Quantity s) -> Arith (Quantity s) # (-) :: Arith (Quantity s) -> Arith (Quantity s) -> Arith (Quantity s) # (*) :: Arith (Quantity s) -> Arith (Quantity s) -> Arith (Quantity s) # negate :: Arith (Quantity s) -> Arith (Quantity s) # abs :: Arith (Quantity s) -> Arith (Quantity s) # signum :: Arith (Quantity s) -> Arith (Quantity s) # fromInteger :: Integer -> Arith (Quantity s) #
KnownNat s => Num (Quantity s) Source #
Instance details Defined in Haspara.Internal.Quantity Methods (+) :: Quantity s -> Quantity s -> Quantity s # (-) :: Quantity s -> Quantity s -> Quantity s # (*) :: Quantity s -> Quantity s -> Quantity s # negate :: Quantity s -> Quantity s # abs :: Quantity s -> Quantity s # signum :: Quantity s -> Quantity s # fromInteger :: Integer -> Quantity s #
Ord (Quantity s) Source #
Instance details Defined in Haspara.Internal.Quantity Methods compare :: Quantity s -> Quantity s -> Ordering # (<) :: Quantity s -> Quantity s -> Bool # (<=) :: Quantity s -> Quantity s -> Bool # (>) :: Quantity s -> Quantity s -> Bool # (>=) :: Quantity s -> Quantity s -> Bool # max :: Quantity s -> Quantity s -> Quantity s # min :: Quantity s -> Quantity s -> Quantity s #
KnownNat s => Show (Quantity s) Source #	`Show` instance for `Quantity`. `>>>` `show (42 :: Quantity 2)`"42.00" `>>>` `42 :: Quantity 2`42.00
Instance details Defined in Haspara.Internal.Quantity Methods showsPrec :: Int -> Quantity s -> ShowS # show :: Quantity s -> String # showList :: [Quantity s] -> ShowS #
Generic (Quantity s) Source #
Instance details Defined in Haspara.Internal.Quantity Associated Types type Rep (Quantity s) :: Type -> Type # Methods from :: Quantity s -> Rep (Quantity s) x # to :: Rep (Quantity s) x -> Quantity s #
KnownNat s => ToJSON (Quantity s) Source #	`ToJSON` instance for `Quantity`. `>>>` `Aeson.encode (quantity 0.42 :: Quantity 2)`"0.42"
Instance details Defined in Haspara.Internal.Quantity Methods toJSON :: Quantity s -> Value # toEncoding :: Quantity s -> Encoding # toJSONList :: [Quantity s] -> Value # toEncodingList :: [Quantity s] -> Encoding #
KnownNat s => FromJSON (Quantity s) Source #	`FromJSON` instance for `Quantity`. `>>>` `Aeson.decode "0.42" :: Maybe (Quantity 2)`Just 0.42 `>>>` `Aeson.decode "0.415" :: Maybe (Quantity 2)`Just 0.42 `>>>` `Aeson.decode "0.425" :: Maybe (Quantity 2)`Just 0.42
Instance details Defined in Haspara.Internal.Quantity Methods parseJSON :: Value -> Parser (Quantity s) # parseJSONList :: Value -> Parser [Quantity s] #
type Rep (Quantity s) Source #
Instance details Defined in Haspara.Internal.Quantity type Rep (Quantity s) = D1 ('MetaData "Quantity" "Haspara.Internal.Quantity" "haspara-0.0.0.1-GIZpgp6So3jGG6B29GnUaf" 'True) (C1 ('MetaCons "MkQuantity" 'PrefixI 'True) (S1 ('MetaSel ('Just "unQuantity") 'NoSourceUnpackedness 'NoSourceStrictness 'DecidedLazy) (Rec0 (Decimal RoundHalfEven s Integer))))

quantity :: KnownNat s => Scientific -> Quantity s Source #

Constructs Quantity values from Scientific values in a lossy way.

This function uses quantityAux in case that the lossless attempt fails. We could have used quantityAux directly. However, quantityAux is doing too much (see roundScientific). Therefore, we are first attempting a lossless construction (see quantityLossless) and we fallback to quantityAux in case the lossless construction fails.

>>> quantity 0 :: Quantity 0
0
>>> quantity 0 :: Quantity 1
0.0
>>> quantity 0 :: Quantity 2
0.00
>>> quantity 0.04 :: Quantity 1
0.0
>>> quantity 0.05 :: Quantity 1
0.0
>>> quantity 0.06 :: Quantity 1
0.1
>>> quantity 0.14 :: Quantity 1
0.1
>>> quantity 0.15 :: Quantity 1
0.2
>>> quantity 0.16 :: Quantity 1
0.2
>>> quantity 0.04 :: Quantity 2
0.04
>>> quantity 0.05 :: Quantity 2
0.05
>>> quantity 0.06 :: Quantity 2
0.06
>>> quantity 0.14 :: Quantity 2
0.14
>>> quantity 0.15 :: Quantity 2
0.15
>>> quantity 0.16 :: Quantity 2
0.16
>>> quantity 0.04 :: Quantity 3
0.040
>>> quantity 0.05 :: Quantity 3
0.050
>>> quantity 0.06 :: Quantity 3
0.060
>>> quantity 0.14 :: Quantity 3
0.140
>>> quantity 0.15 :: Quantity 3
0.150
>>> quantity 0.16 :: Quantity 3
0.160

quantityAux :: forall s. KnownNat s => Scientific -> Quantity s Source #

Auxiliary function for quantity implementation.

See quantity why we need this function and why we haven't used it as the direct implementation of quantity.

Call-sites should avoid using this function directly due to its performance characteristics.

quantityLossless :: (KnownNat s, MonadError String m) => Scientific -> m (Quantity s) Source #

Constructs Quantity values from Scientific values in a lossy way.

>>> quantityLossless 0 :: Either String (Quantity 0)
Right 0
>>> quantityLossless 0 :: Either String (Quantity 1)
Right 0.0
>>> quantityLossless 0 :: Either String (Quantity 2)
Right 0.00
>>> quantityLossless 0.04 :: Either String (Quantity 1)
Left "Underflow while trying to create quantity: 4.0e-2"
>>> quantityLossless 0.05 :: Either String (Quantity 1)
Left "Underflow while trying to create quantity: 5.0e-2"
>>> quantityLossless 0.06 :: Either String (Quantity 1)
Left "Underflow while trying to create quantity: 6.0e-2"
>>> quantityLossless 0.14 :: Either String (Quantity 1)
Left "Underflow while trying to create quantity: 0.14"
>>> quantityLossless 0.15 :: Either String (Quantity 1)
Left "Underflow while trying to create quantity: 0.15"
>>> quantityLossless 0.16 :: Either String (Quantity 1)
Left "Underflow while trying to create quantity: 0.16"
>>> quantityLossless 0.04 :: Either String (Quantity 2)
Right 0.04
>>> quantityLossless 0.05 :: Either String (Quantity 2)
Right 0.05
>>> quantityLossless 0.06 :: Either String (Quantity 2)
Right 0.06
>>> quantityLossless 0.14 :: Either String (Quantity 2)
Right 0.14
>>> quantityLossless 0.15 :: Either String (Quantity 2)
Right 0.15
>>> quantityLossless 0.16 :: Either String (Quantity 2)
Right 0.16
>>> quantityLossless 0.04 :: Either String (Quantity 3)
Right 0.040
>>> quantityLossless 0.05 :: Either String (Quantity 3)
Right 0.050
>>> quantityLossless 0.06 :: Either String (Quantity 3)
Right 0.060
>>> quantityLossless 0.14 :: Either String (Quantity 3)
Right 0.140
>>> quantityLossless 0.15 :: Either String (Quantity 3)
Right 0.150
>>> quantityLossless 0.16 :: Either String (Quantity 3)
Right 0.160

roundQuantity :: KnownNat k => Quantity (n + k) -> Quantity n Source #

Rounds given quantity by k digits.

>>> roundQuantity (quantity 0.415 :: Quantity 3) :: Quantity 2
0.42
>>> roundQuantity (quantity 0.425 :: Quantity 3) :: Quantity 2
0.42

times :: (KnownNat s, KnownNat k) => Quantity s -> Quantity k -> Quantity s Source #

Multiplies two quantities with different scales and rounds back to the scale of the frst operand.

>>> times (quantity 0.42 :: Quantity 2) (quantity 0.42 :: Quantity 2)
0.18

timesLossless :: (KnownNat s, KnownNat k) => Quantity s -> Quantity k -> Quantity (s + k) Source #

Multiplies two quantities with different scales.

>>> timesLossless (quantity 0.42 :: Quantity 2) (quantity 0.42 :: Quantity 2)
0.1764

roundScientific :: Int -> Scientific -> Scientific Source #

Rounds a given scientific into a new scientific with given max digits after decimal point.

This uses half-even rounding method.

>>> roundScientific 0 0.4
0.0
>>> roundScientific 0 0.5
0.0
>>> roundScientific 0 0.6
1.0
>>> roundScientific 0 1.4
1.0
>>> roundScientific 0 1.5
2.0
>>> roundScientific 0 1.6
2.0
>>> roundScientific 1 0.04
0.0
>>> roundScientific 1 0.05
0.0
>>> roundScientific 1 0.06
0.1
>>> roundScientific 1 0.14
0.1
>>> roundScientific 1 0.15
0.2
>>> roundScientific 1 0.16
0.2
>>> roundScientific 1 3.650
3.6
>>> roundScientific 1 3.740
3.7
>>> roundScientific 1 3.749
3.7
>>> roundScientific 1 3.750
3.8
>>> roundScientific 1 3.751
3.8
>>> roundScientific 1  3.760
3.8
>>> roundScientific 1 (-3.650)
-3.6
>>> roundScientific 1 (-3.740)
-3.7
>>> roundScientific 1 (-3.749)
-3.7
>>> roundScientific 1 (-3.750)
-3.8
>>> roundScientific 1 (-3.751)
-3.8
>>> roundScientific 1 (-3.760)
-3.8

TODO: Refactor to improve the performance of this function.

Orphan instances

Lift (Decimal RoundHalfEven s Integer :: Type) Source #

Orphan Lift instance for Quantity.

TODO: Avoid having an orphan instance for Decimal r s p?

Instance details

Methods

lift :: Decimal RoundHalfEven s Integer -> Q Exp #

liftTyped :: Decimal RoundHalfEven s Integer -> Q (TExp (Decimal RoundHalfEven s Integer)) #