racket/collects/math/private/functions/lanczos.rkt
Neil Toronto f2dc2027f6 Initial math library commit. The history for these changes is preserved
in the original GitHub fork:

  https://github.com/ntoronto/racket

Some things about this are known to be broken (most egregious is that the
array tests DO NOT RUN because of a problem in typed/rackunit), about half
has no coverage in the tests, and half has no documentation. Fixes and
docs are coming. This is committed now to allow others to find errors and
inconsistency in the things that appear to be working, and to give the
author a (rather incomplete) sense of closure.
2012-11-16 11:39:51 -07:00

39 lines
1.1 KiB
Racket

#lang typed/racket/base
(require "../../flonum.rkt")
(provide lanczos-sum lanczos-g)
;; Lanczos polynomial for N=13 G=6.024680040776729583740234375
;; Max experimental error (with arbitary precision arithmetic) is 1.196214e-17
(define lanczos-sum
(make-quotient-flpolyfun
(23531376880.41075968857200767445163675473
42919803642.64909876895789904700198885093
35711959237.35566804944018545154716670596
17921034426.03720969991975575445893111267
6039542586.35202800506429164430729792107
1439720407.311721673663223072794912393972
248874557.8620541565114603864132294232163
31426415.58540019438061423162831820536287
2876370.628935372441225409051620849613599
186056.2653952234950402949897160456992822
8071.672002365816210638002902272250613822
210.8242777515793458725097339207133627117
2.506628274631000270164908177133837338626)
(0.0
39916800.0
120543840.0
150917976.0
105258076.0
45995730.0
13339535.0
2637558.0
357423.0
32670.0
1925.0
66.0
1.0)))
(define lanczos-g 6.024680040776729583740234375)