Fourier Transform

https://betterexplained.com/topics/fourier-transform/

What does the Fourier Transform do? Given a smoothie, it finds the recipe.

How? Run the smoothie through filters to extract each ingredient.

Why? Recipes are easier to analyze, compare, and modify than the smoothie itself.

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FT is a mathematical transform that decomposes functions depending on space or time into functions depending on spatial frequency or temporal frequency. That process is also called analysis.

An example application would be decomposing the waveform of a musical chord into terms of the intensity of its constituent pitches.

The term Fourier transform refers to both the frequency domain representation and the mathematical operation that associates the frequency domain representation to a function of space or time.