Safe Haskell | None |
---|---|
Language | Haskell98 |
Data.Number.Erf
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
Nothing
Methods
Arguments
:: a | |
-> a | erfc x = 1 - erf x |
Arguments
:: a | |
-> a | erfcx x = exp (x*x) * erfc x |
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