Fourier transform: Difference between revisions

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In most languages, FFT is defined as:
In most languages, FFT is defined as:
<math display="block">A_k = \sum_{0}^{n-1} f(x) \exp\ \left\{ -2 \pi i \frac{mk}{n} \right\}</math>
<math display="block">A_k = \sum_{m=0}^{n-1} f(x) \exp\ \left\{ -2 \pi i \frac{mk}{n} \right\}</math>
and IFFT is defined as:
and IFFT is defined as:
<math display="block">a_m = \frac{1}{n} \sum_{0}^{n-1} \hat{f}(\xi) \exp \left\{ 2 \pi i \frac{mk}{n} \right\}</math>
<math display="block">a_m = \frac{1}{n} \sum_{k=0}^{n-1} \hat{f}(\xi) \exp \left\{ 2 \pi i \frac{mk}{n} \right\}</math>


==Properties==
==Properties==