dft-for-finite-groups-over-various-fields

Implements the discrete Fourier transform for the cyclic group and symmetric group over finite fields, and number fields in the unitary case.

For finite fields, when $p$ divides $|G|$ we use the modular DFT, which is given by the Peirce decomposition using central primitive orthogonal idempotents.

See: The Modular DFT of the Symmetric Group