scijs / fourier-transform Goto Github PK

//get normalized magnitudes for frequencies from 0 to 22050 with interval 44100/1024 ≈ 43Hz

Is it possible to change the precision from 1024 to 4096?

Hi,

I suppose I'm neither the first of or the last that, frustrated by the abandon of dsp.js library, tries to maintain an updated version of the bests parts. So, I've started a port of rsft (before discover your project): https://github.com/oramics/dsp-kit/tree/master/packages/rfft

I also did my own benchmarks (at least repeating is good for learn ;-). Finally I've tried to include the inverse rfft implementation: https://github.com/oramics/dsp-kit/blob/master/packages/rfft/lib/inverse.js

But the problem is that I discover that this rfft implementation returns a result that is completely different from the fftimplementation of the same dsp.js library. The test is here: https://github.com/oramics/dsp-kit/blob/master/packages/rfft/test/test.js#L7

Have you tested the output? Are you aware of this problem? Did you used this implementation in any project?

Thanks in advance.

Great work! I've been wishing for a nice clean implementation for a long time! One small thing: Is it possible to clarify in the readme whether this works non-power-of-two sizes? It wasn't immediately clear to me from either the readme or the source which sizes are permitted (or if there are restrictions at all). Thanks!

Implement dsp.js' FFT for complex numbers.

I am having issues with the FFT() function, the output im receiving is always NaN, and i cannot figure out why. Any help would be appreciated. I am using ReactNative as such my code snippet is as follows:

      let tempx = []
      let tempy = []
      let tempz = []

      for(var i =0;i<1024;i++){
        tempx[i] = parseFloat(arrayx[i])
        tempy[i] = parseFloat(arrayy[i])
        tempz[i] = parseFloat(arrayz[i])
      }

      let spectrumx = ft(tempx);
      let spectrumy = ft(tempy);
      let spectrumz = ft(tempz);

For reference see ndarray-fft, Bluestein’s FFT.

$ node --version
v6.12.3
$ node
> var db = require('decibels');

module.js:471
    throw err;
    ^

Error: Cannot find module 'decibels'
    at Function.Module._resolveFilename (module.js:469:15)
    at Function.Module._load (module.js:417:25)
    at Module.require (module.js:497:17)
    at require (internal/module.js:20:19)
    at Object.<anonymous> (/usr/lib/test/code.js:96:10)
    at Module._compile (module.js:570:32)
    at Object.Module._extensions..js (module.js:579:10)
    at Module.load (module.js:487:32)
    at tryModuleLoad (module.js:446:12)
    at Function.Module._load (module.js:438:3)

> var ft = require('fourier-transform');
undefined
> ft
[Function: rfft]
>