The Fast Fourier Transform

http://jeremykun.wordpress.com/2012/07/18/the-fast-fourier-transform/

by signa11 • 14 years ago

116 11 14 years ago

jeremykun.wordpress.com

Hitchhiker• 14 years ago

" As noted by his former pupil and collaborator André Deprit, Lemaître was one of the inventors of the modern Fast Fourier Transform technique.

Lemaître was well ahead on his time regarding machine computing. As early as the thirties at MIT, he used the machine perfected by Bush to solve the Störmer problem. "

source : http://www.uclouvain.be/en-316446.html

rodh• 14 years ago

Wow. I hadn't come accross this blog before. It has a fantastic wealth of content, all relevant to my interests. Very impressed.

jpdevereaux• 14 years ago

I stumbled across this site a while ago when learning about Neural Networks. Never even realized what a broad range of other interesting topics he covered.

textminer• 14 years ago

Love his tutorials. Motivates PCA by walking trough a creepy eigenface decomposition, and solves a political prediction problem with a ID3 implementation of a decision tree. I actually used the latter initial code scrap for writing an entire damn random forest implementation!

Really looking forward to his future discussion of computational topology and persistent homologies.

ctchocula• 14 years ago

Seems like a great blog. I'm trying to get through The Road to Reality by Roger Penrose that's supposedly capable of giving a layman an idea of the math and physics behind modern physics including string theory, but I'm finding Jeremy Kun's treatment of some of the same mathematical concepts using animation and colloquial language to be easier to understand.

OldSchool• 14 years ago

Great content! Nice mix of math, backstory and practical examples along the way to keep the reader engaged.

I was a little concerned that the Python cmath library might be written in Python but from what I can tell, it's native-code from C.

jamesgeck0• 14 years ago

Yep! In general, any Python library prefixed with a C will be native.

napoleond• 14 years ago

Excellent article! In case anyone has use for it, the other day I wrote a quick little javascript implementation of the FFT for inclusion in sjkaliski's numbers.js[0]. It hasn't been merged in yet, but my implementation[1] is tiny and (hopefully) easy to read. (complex.js and dsp.js work fine on their own, without the rest of numbers.js)

[0] https://github.com/sjkaliski/numbers.js

[1] https://github.com/napoleond/numbers.js/blob/master/lib/numb...

agentq• 14 years ago

For anyone who doesn't want to roll their own FFT, take a look at this excellent pure C implementation: http://www.fftw.org/

j2kun• 14 years ago

This is a parallel agorithm...

guan• 14 years ago

When you present the Fourier transform as frequency spectrum, what are you actually plotting? Magnitude? Real part?

The Fast Fourier Transform

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