This article specifically discusses Fourier transformation of functions on the
real line; for other kinds of Fourier transformation, see
Fourier analysis and
list of Fourier-related transforms. In
mathematics, the Fourier transform, named in honor of French mathematician
Joseph Fourier, is a certain
linear operator that maps
functions to other functions. Loosely speaking, the Fourier transform decomposes a function into a continuous spectrum of its frequency components, and the inverse transform synthesizes a function from its spectrum of frequency components. A useful analogy is the relationship between a set of notes in musical
notation (the frequency components) and the sound of the musical chord represented by these notes (the function/signal itself).
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