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In article <1993Jan25.201447.2082@athena.mit.edu>, cai@athena.mit.edu (Liang-Wu Cai) writes:
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|>From: cai@athena.mit.edu (Liang-Wu Cai)
|>Subject: Algorithm(s) need for Bessel functions
|>Message-ID: <1993Jan25.201447.2082@athena.mit.edu>
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|>Date: Mon, 25 Jan 1993 20:14:47 GMT
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|>
|>Dear netter,
|>
|> I am in need (badly) of an accurate algorithm Bessel functions of various 
|>kinds with real argument and integer order. What I need actually is a 
|>algorithm which is able to provide the result with at least 7 significant 
|>digits for J_n (z) and Y_n (z) with n <=100 and z <= 100.

Look into Abromowitz/Stegun Handbook of Mathamatical Functions:

1.) set j(100)=0
2.) set j(99)=1
3.) do recursion to j(0)
4.) calculate the true j(0) in order to define a normalisation faktor
5.) Multiply all value with that factor

You get all values J(0)...j(100) in that way.

Eberhard Heuser-Hofmann