qfb_nucomp
Synopsis
#include <flint/qfb.h>Sets r to a form in the class of the composition of f and g, both of discriminant D, by Shanks' NUCOMP algorithm in the version of Jacobson and van der Poorten [JvdP2002], with a partial Lehmer extended GCD (fmpz_xgcd_partial). The parameter must be L = \lfloor |D|^{1/4} \rfloor. The result is nearly reduced (its coefficients are of the size of \sqrt{|D|}) but must be passed to qfb_reduce to obtain the reduced form. f must be primitive.
Guides#
References#
- [JvdP2002] M. J. Jacobson Jr. and A. J. van der Poorten. "Computational aspects of NUCOMP." In International Algorithmic Number Theory Symposium, pp. 120-133. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002.
Cite this page
The FLINT team, “qfb_nucomp (qfb.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/qfb/qfb_nucomp.html (generated 2026-10-20).
@misc{flint-doc-qfb-qfb-nucomp,
author = {{The FLINT team}},
title = {{qfb\_nucomp (qfb.h)}},
howpublished = {FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev},
year = {2026},
url = {https://flintlib.org/doc/qfb/qfb_nucomp.html},
note = {Generated 2026-10-20}
}