Function Description

The Fast Fourier Transform (FFT) library contains a series of interface for FFT functions. The KML_FFT library contains the following four types of functions:

• Plan functions: used to create a plan for an FFT. After a plan is used, call the kml_fft(f)_destroy_plan function to release it.
  • C2C Transforms: FFT from one complex number to another
  • R2C Transforms: FFT from a real number form to a complex number
  • C2R Transforms: FFT from a complex number to a real number
  • R2R Transforms: FFT from a real number to a real number
• Execution functions: used to execute an FFT based on the plan.
• Memory functions: used to allocate and release a memory space.
• Thread functions: used to initialize threads and release related resources.

For the previous transforms, the KML_FFT library supports:

• In-place transform (the input and output have the same pointer) and out-place transform.
• Single precision and double precision: Single-precision functions use kml_fftf_ as the function prefix, and double-precision functions use kml_fft_ as the function prefix. Function Syntax provides examples of double-precision functions.