FLINT3.7.0-dev
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_fq_nmod_poly_compose_mod_brent_kung, fq_nmod_poly_compose_mod_brent_kung, _fq_nmod_poly_compose_mod_brent_kung_preinv, fq_nmod_poly_compose_mod_brent_kung_preinv

Synopsis#include <flint/fq_nmod_poly.h>
void _fq_nmod_poly_compose_mod_brent_kung(fq_nmod_struct * res, const fq_nmod_struct * poly1, slong len1, const fq_nmod_struct * poly2, const fq_nmod_struct * poly3, slong len3, const fq_nmod_ctx_t ctx)
void fq_nmod_poly_compose_mod_brent_kung(fq_nmod_poly_t res, const fq_nmod_poly_t poly1, const fq_nmod_poly_t poly2, const fq_nmod_poly_t poly3, const fq_nmod_ctx_t ctx)
void _fq_nmod_poly_compose_mod_brent_kung_preinv(fq_nmod_struct * res, const fq_nmod_struct * poly1, slong len1, const fq_nmod_struct * poly2, const fq_nmod_struct * poly3, slong len3, const fq_nmod_struct * poly3inv, slong len3inv, const fq_nmod_ctx_t ctx)
void fq_nmod_poly_compose_mod_brent_kung_preinv(fq_nmod_poly_t res, const fq_nmod_poly_t poly1, const fq_nmod_poly_t poly2, const fq_nmod_poly_t poly3, const fq_nmod_poly_t poly3inv, const fq_nmod_ctx_t ctx)

Modular composition f(g) mod hf(g) \bmod h by the Brent–Kung algorithm: the powers gi mod hg^i \bmod h for i<m=⌈lenf⌉i < m = \lceil \sqrt{\mathit{lenf}} \rceil are computed, ff is split into mm blocks, the block compositions are obtained by one m×mm \times m by m×deg⁡hm \times \deg h matrix product, and the results are combined by Horner's rule in gmg^m. Requires deg⁡f<deg⁡h\deg f < \deg h and gg reduced modulo hh; the _preinv versions also require the inverse of the reversal of hh. No aliasing in the underscore versions.

Generated from the same template as _fq_poly_compose_mod_brent_kung, whose documentation has the details.

Cite this page

The FLINT team, “_fq_nmod_poly_compose_mod_brent_kung, fq_nmod_poly_compose_mod_brent_kung, _fq_nmod_poly_compose_mod_brent_kung_preinv, fq_nmod_poly_compose_mod_brent_kung_preinv (fq_nmod_poly.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/fq_nmod_poly/_fq_nmod_poly_compose_mod_brent_kung.html (generated 2026-11-02).