libclfft-dev binary package in Ubuntu Focal amd64

 The clFFT library is an open source OpenCL library implementation of discrete
 Fast Fourier Transforms, which:
 .
   * Provides a fast and accurate platform for calculating discrete FFTs.
   * Works on CPU or GPU backends.
   * Supports in-place or out-of-place transforms.
   * Supports 1D, 2D, and 3D transforms with a batch size that can be greater
     than 1.
   * Supports planar (real and complex components in separate arrays) and
     interleaved (real and complex components as a pair contiguous in memory)
     formats.
   * Supports dimension lengths that can be any mix of powers of 2, 3, and 5.
   * Supports single and double precision floating point formats.
 .
 This package provides the development files.

Source package