Fourier transform: Difference between revisions

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'''Parseval's Theorem'''<br>
'''Parseval's Theorem'''<br>
<math>\int |f(x)|^2 dx = \int |F(s)|^2 ds</math>
<math>\int |f(x)|^2 dx = \int |F(s)|^2 ds</math>
See [[Wikipedia: Parseval's theorem]]<br>
See [[Wikipedia: Parseval's theorem]]<br>


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'''Autocorrelation'''<br>
'''Autocorrelation'''<br>
<math>\int f(x') f^*(x' - x) dx' \Leftrightarrow |F(x)|^2</math>
<math>\int f(x') f^*(x' - x) dx' \Leftrightarrow |F(x)|^2</math>
This is a case of the convolution theorem.
This is a case of the convolution theorem.