ffts-and-unlucky-primes.html

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         title="Permalink to FFTs and unlucky primes">FFTs and unlucky primes</a></h2>
 
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    <abbr class="published" title="2008-08-12T17:04:00-06:00">
      2008/08/12
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      By <a class="url fn" href="https://keflavich.github.io/blog/author/adam-adamgginsburggmailcom.html">Adam (adam.g.ginsburg@gmail.com)</a>
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    <p>I've encountered a lot (!) of unlucky prime numbers that I'm trying to
FFT in too many places, and it basically stops the code.
211151 was impossibly bad, 5827 is pretty bad too.
I solved the first by splitting into by-scan delining, which is better
anyway. But the second is a map, in which I KNOW zero padding is OK.
So... are there any functions that find the nearest reasonably efficient
map size?</p>

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