_fft_small_np2_choose
Synopsis
#include <flint/fft_small.h>int _fft_small_np2_choose(const mpn_ctx_struct * R, ulong an, ulong bn, ulong len_bound, ulong * bits, ulong * depth)sourceChooses the least depth d \in [8, 30] and then the largest chunk size b \in [40, 45] with \lceil 64 a_n / b \rceil + \lceil 64 b_n / b \rceil - 1 \le 2^d and len_bound \cdot \lceil 64 b_n / b \rceil \cdot 2^{2b} < p_0 p_1. Returns 0 if there is none.
Cite this page
The FLINT team, “_fft_small_np2_choose (fft_small.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/fft_small/_fft_small_np2_choose.html (generated 2026-10-20).
@misc{flint-doc-fft-small-fft-small-np2-choose,
author = {{The FLINT team}},
title = {{\_fft\_small\_np2\_choose (fft\_small.h)}},
howpublished = {FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev},
year = {2026},
url = {https://flintlib.org/doc/fft_small/_fft_small_np2_choose.html},
note = {Generated 2026-10-20}
}