What is Fourier analysis?
{{no sources|date=October 2021}} [[File:Fourier_transform_time_and_frequency_domains_(small).gif|frame|right|A visual representation of a fourier transform, the time axis is shown in red, the [[frequency]] axis is shown in blue. Since the time signal is periodic, it only shows certain parts of the [[spectrum]]]] {{Fourier transforms}} '''Fourier analysis''' is a branch of [[analysis ]] that looks at how more complex [[function (mathematics)|functions]] can be built with simpler ones. It is also known as '''classical harmonic analysis'''. It is named after [[Joseph Fourier]] who first used it in the 19th century. The process itself is called [[Fourier transform]]. Fourier analysis is widely used in fields such as [[physics]], [[partial differential equation]]s, [[number theory]], [[combinatorics]], [[signal processing]], imaging, [[probability theory]], [[statistics]], [[option pricing]], [[cryptography]], [[numerical analysis]], [[acoustics]], [[oceanography]], [[sonar]], [[optics]], [[diffraction]], [[geometry]] and [[protein]] structure analysis. {{Statistics}} {{math-stub}} [[Category:Functions and mappings]] [[Category:Harmonic analysis]]