_fft_small_len_trunc, _fft_small_op_trunc
Synopsis
#include <flint/fft_small.h>_fft_small_len_trunc(x)source_fft_small_op_trunc(x, P)sourceThe truncation of an operand or output of length x: x rounded up to a multiple of 256 or, below one block, the full transform length. _fft_small_len_trunc anticipates it before a plan exists, using the length 2^{\max(4, \lceil \log_2 x \rceil)} below 256; _fft_small_op_trunc gives the one the plan P imposes, 2^d for a depth d < 8.
Guides#
Cite this page
The FLINT team, “_fft_small_len_trunc, _fft_small_op_trunc (fft_small.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/fft_small/_fft_small_len_trunc.html (generated 2026-10-20).
@misc{flint-doc-fft-small-fft-small-len-trunc,
author = {{The FLINT team}},
title = {{\_fft\_small\_len\_trunc, \_fft\_small\_op\_trunc (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_len_trunc.html},
note = {Generated 2026-10-20}
}