erf-2.0.0.0: The error function, erf, and related functions.
Safe Haskell None
Language Haskell98

Data.Number.Erf

Synopsis

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 (x*x) * erfc x

normcdf Source #

Arguments

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

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