Fourier transform: Difference between revisions

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<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>
<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>


That the main different between the FFT and IFFT is the negative symbol in the exponent.
That the main difference between the FFT and IFFT is the negative symbol in the exponent.
You can implement IFFT as <code>IFFT(x) = (1/len(x))*conj(FFT(conj(x)))</code><ref name="siembida2010ifft"></ref>.
You can implement IFFT as <code>IFFT(x) = (1/len(x))*conj(FFT(conj(x)))</code><ref name="siembida2010ifft"></ref>.