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Message ID: 10     Entry time: Wed Jun 5 16:59:51 2013
Author: Matt A. 
Type: Optics 
Category: General 
Subject: Matlab code for calculating the zeros of Bessel functions from GWINC 

 For calculating the Liu and Thorn U_0 + DU, you need to sum over the first N zeros of the first-order Bessel function. Unfortunately, Matlab doesn't seem to come with a function to do this.

 

Rather than re-invent the wheel, we can just use the function used by GWINC.

Attachment 1: besselzero.m  1 kB  | Hide | Hide all
function x=besselzero(n,k,kind)

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%
% besselzero.m
%
% Find first k positive zeros of the Bessel function J(n,x) or Y(n,x) 
% using Halley's method.
%
% Written by: Greg von Winckel - 01/25/05
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