Math.NumberTheory.Zeta.Riemann

Riemann zeta-function.

Documentation

zetas :: (Floating a, Ord a) => a -> [a]

Infinite sequence of approximate (up to given precision) values of Riemann zeta-function at integer arguments, starting with ζ(0). Computations for odd arguments are performed in accordance to Computational strategies for the Riemann zeta function by J. M. Borwein, D. M. Bradley, R. E. Crandall, formula (57).

>>> take 5 (zetas 1e-14) :: [Double]
> [-0.5,Infinity,1.6449340668482262,1.2020569031595942,1.0823232337111381]

Beware to force evaluation of zetas !! 1, if the type a does not support infinite values (for instance, Fixed).

zetasEven :: [ExactPi]

Infinite sequence of exact values of Riemann zeta-function at even arguments, starting with ζ(0). Note that due to numerical errors conversion to Double may return values below 1:

>>> approximateValue (zetasEven !! 25) :: Double
0.9999999999999996

Use your favorite type for long-precision arithmetic. For instance, Fixed works fine:

>>> import Data.Number.Fixed
>>> approximateValue (zetasEven !! 25) :: Fixed Prec50
1.00000000000000088817842111574532859293035196051773

zetasOdd :: forall a. (Floating a, Ord a) => a -> [a]