Category:Definitions/Fourier Transforms

From ProofWiki
Jump to navigation Jump to search

This category contains definitions related to Fourier Transforms.
Related results can be found in Category:Fourier Transforms.

The Fourier transform of a Lebesgue integrable function $f: \R^N \to \C$ is the function $\map \FF f: \R^N \to \C$ given by:

$\displaystyle \map \FF {\map f \xi} := \int_{\R^N} \map f {\mathbf x} e^{-2 \pi i \mathbf x \cdot \xi} \rd \mathbf x$

for $\xi \in \R^N$.

Here, the product $\mathbf x \cdot \xi$ in the exponential is the dot product of the vectors $\mathbf x$ and $\mathbf \xi$.