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Re: Journal of negative results in Octave?

From: Jose Ramom Flores das Seixas
Subject: Re: Journal of negative results in Octave?
Date: Thu, 26 Sep 2019 14:34:51 +0200
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0

Às 18:03 de 23/09/19, Nir Krakauer escreveu:
Looks like nice work. arXiv may be a good place to quickly post such a
result where anyone can find it, and a repository like BitBucket or
GitLab for making the program developed available.

Thank for your suggestions.

On Mon, Sep 23, 2019 at 11:42 AM Jose Ramom Flores das Seixas
<address@hidden> wrote:
I would like to know if there is something like The negative results Journal 
for octave functions?

The reason I ask is because I implemented a quadrature for strongly oscillating 
functions, quadgF, but after comparing it with octave function quadgk I found, 
to my disappointment, that my function was not generally faster than quadgk.

The quadgk and quadl functions allowed to integrate strongly oscillating 
functions, but they are slow for my needs: perform diffraction calculations. 
Browsing the bibliography on the subject, I found an article by L.F. Shampine, 
reference [1], which describes an algorithm that seemed easy to implement to 
me. In fact, the proposed algorithm is an improvement of the SSP method [2,3], 
which possibly Mr. Shampine did not know, since he does not mention it in his 

In his article, Professor Shampine talks about a function he implemented, 
quadgF, based on the algorithm, but as much as I looked for it I couldn't find 
it -quadgF.m-. So I implemented it as well as I could, trying to vectorize it 
as much as possible, and kept the name used in [1].
It is quite possible that the reason why Professor Shampine's function has 
disappeared from the radar is precisely what I found after writing my 
implementation, i.e. that, in general, has no advantages over general functions 
like quadgk.
Anyway, for if my implementation served someone, either because he/she improved 
it and got more speed, or to avoid wasting time doing what I already did, I 
send attached the function I wrote, quadgF.m, and a document, quadgF.pdf, 
describing the algorithm and my implementation, as well as an analysis that 
compares my function and quadgk.
Yours sincerely
Jose Ramom


1Shampine L.F., Integrating oscillatory functions in MATLAB, II. Electronic 
Transactions on Numerical Analysis, volume 39, pp 403-413, 2012.
2Stamnes J.J., Spjelkavik B. & Pedersen H.M., Evaluation of diffraction 
integrals using local phase and amplitude approximations. Opt. Acta 30, 207-222, 
3Stamnes J.J., Waves in focal regions: propagation, diffraction and focusing of 
light, sound and water waves. Adam Hilger, 1986.

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