Re: Where I find Bessel function for Ada ?

[Ken Thomas <kst@ecs.soton.ac.uk>]

On Nov 26, 1:08 pm, Paul Cole Gloster <Colin_Paul_Glos...@ACM.org>
wrote:
> Reinert submitted:
>
> |----------------------------------------------------------------|
> |"I want to use the modified Bessel function of order 0 in my Ada|
>
> |program.                                                        |
>
> |                                                                |
>
> |Where I find it ?"                                              |
> |----------------------------------------------------------------|
>
> It may be best to write your own version so that you could justifiably
> have an accurate level of confidence of it.
>
> Gautier responded:
>
> !---------------------------------------------------------------!
> !"It is in the Numerical Recipes in Pascal, chapter 6.4, pp 191.!
>
> !All you need to pick the right Pascal source, like bessj0.pas  !
>
> !and put it through th P2Ada translator:http://p2ada.sf.net/  !
>
> !The NR sources are freely available on the Internet."          !
> !---------------------------------------------------------------!
>
> I have not thoroughly assessed that particular part of "Numerical
>
> Recipes", but some parts of "Numerical Recipes" are
> untrustworthy. Early in 2009 on
> WWW.ACCU.org
> a review by myself which is almost ready for publication should be
> available.

The source for the Pascal version of Numerical Recipes can be found at
http://archives.math.utk.edu/software/msdos/numerical.analysis/nrpas13/.html

As the code for bessj0 is very short, translation to Ada is a small
exercise. On the other hand, the code seems to deal with only single
precision arithmetic so does not promise high accuracy.

Ken