bigfloats of special functions (e.g. Bessel).. wasRe: integrate bessel_j errcatch?
Subject: bigfloats of special functions (e.g. Bessel).. wasRe: integrate bessel_j errcatch?
From: Richard Fateman
Date: Thu, 08 Dec 2011 11:18:50 -0800
On 12/8/2011 11:05 AM, Raymond Toy wrote:
>
>
> On Thu, Dec 8, 2011 at 9:30 AM, Richard Fateman
> <fateman at eecs.berkeley.edu <mailto:fateman at eecs.berkeley.edu>> wrote:
>
> On 11/9/2011 12:44 PM, Barton Willis wrote:
>
> In addition to being slow, only the 2F1 hypergeometric
> function analytically continues to outside the convergence disk.
>
> --Barton
>
>
> I have been looking around at the literature on "unrestricted
> algorithms" for elementary and special functions,
> esp. work by Richard Brent.
>
> These are algorithms appropriate for bigfloats in that instead of
> compute sin(x), or bessel_j(0,x),
> for a given x, take another parameter n, where n is the number
> of bits of precision required.
>
>
> Do you have a link? I looked sometime ago for some algorithms for
> bessel functions and only found one using Hadamard series
> (http://www.sciencedirect.com/science/article/pii/S0377042708001799)
> and some variations thereof. Never got them to converge but I only
> spent a short time on them. The algorithms weren't difficult, but I
> was not smart enough to get them to converge.
>
> Ray
I started with
http://arxiv.org/PS_cache/arxiv/pdf/1004/1004.3621v1.pdf by Richard Brent
which seems to be dated 2010, and has lots of references.
RJF