Safe Haskell	None
Language	Haskell98

Data.Number.Erf

Synopsis

class Floating a => Erf a where
- erf :: a -> a
- erfc :: a -> a
- erfcx :: a -> a
- normcdf :: a -> a
class Floating a => InvErf a where
- inverf :: a -> a
- inverfc :: a -> a
- invnormcdf :: a -> a

Documentation

class Floating a => Erf a where Source #

Error function related functions.

The derivative of erf is x -> 2 / sqrt pi * exp (x^2), and this uniquely determines erf by erf 0 = 0.

Minimal complete definition is erfc or normcdf.

Minimal complete definition

Nothing

Methods

erf :: a -> a Source #

erfc Source #

Arguments

:: a
-> a	erfc x = 1 - erf x

erfcx Source #

Arguments

:: a
-> a	erfcx x = exp (xx) erfc x

normcdf Source #

Arguments

:: a
-> a	normcdf x = erfc(-x sqrt 2) 2

Instances

Erf Double Source #
Instance details Defined in Data.Number.Erf Methods erf :: Double -> Double Source # erfc :: Double -> Double Source # erfcx :: Double -> Double Source # normcdf :: Double -> Double Source #
Erf Float Source #
Instance details Defined in Data.Number.Erf Methods erf :: Float -> Float Source # erfc :: Float -> Float Source # erfcx :: Float -> Float Source # normcdf :: Float -> Float Source #

class Floating a => InvErf a where Source #

Inverse error functions, e.g., inverf . erf = id and erf . inverf = id assuming the appropriate codomain for inverf. Note that the accuracy may drop radically for extreme arguments.

Minimal complete definition

invnormcdf

Methods

inverf :: a -> a Source #

inverfc :: a -> a Source #

invnormcdf :: a -> a Source #

Instances

InvErf Double Source #
Instance details Defined in Data.Number.Erf Methods inverf :: Double -> Double Source # inverfc :: Double -> Double Source # invnormcdf :: Double -> Double Source #
InvErf Float Source #
Instance details Defined in Data.Number.Erf Methods inverf :: Float -> Float Source # inverfc :: Float -> Float Source # invnormcdf :: Float -> Float Source #