Module fft

The fft module itself contains some basic functions ;ole dft, and idft functions. Other fast fourier transform algorithms are exported through crates like,

Algorithm	Module Name
Cooley-Tukey	ct
Chirp-Z Transform (Bluestein’s Algorithm)	czt

The most common use case tends to be computing the FFT of a real-valued input collection producting a complex output collection. The opposite for computing the IFFT. Thus, by default implementations should expose an fft, and ifft function meeting the most common use case, and a purely complex implementation is exposed through the algorithm’s complex module. For example, the cooley-tukey implementation exposes

• ct::fft
• ct::ifft
• ct::complex::fft
• ct::complex::ifft

Modules

• complex
• ct
• czt

Functions

• dft
  Computes the discrete fourier tranform on the real valued input collection
• dtft
  Compute the discrete time fourier transform of the real valued input collection. Returns a closure which accepts a collection of sample frequencies and returns a collection of the fft values
• fftfreq
  Computes the frequency values associated fft based on n the length of the collection and d the sampling period
• fftfreq_balanced
  Computes the frequency values associated fft based on n the length of the collection and d the sampling period but the frequency values are symmetric about the y-axis i.e. same the scipy’s fftfreq function
• idft
  Computes the inverse discrete fourier transform of the real valued input collection. The output is normalized
• wrap_phase
  Wraps an angle in radians to the range (-π, π].