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Message ID: 12     Entry time: Wed Jun 5 20:54:59 2013
Author: Deep Chatterjee 
Type: General 
Category: General 
Subject: Bessel Function roots 

During the process of evaluating the PSD from Sec. V of Liu and Thorn, I chanced to write a simpler root finding algorithm applying bisection to find the roots of J1(x).

The difference between this and the algorithm by

Greg von Winckel goes as
Difference_between_algorithms.png

The difference is of the order 10-7 and can be reduced by reducing the tolerance. However, It should however be noted that bisection is a crude algorithm for rough usage and differences become pronounced for larger n.

 

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