_fq_poly_sqrt, fq_poly_sqrt
Synopsis
#include <flint/fq_poly.h>If the polynomial is the square of a polynomial, set the output to a square root and return 1; otherwise return 0. The underscore version writes len / 2 + 1 coefficients.
In characteristic 2 a square is a polynomial in x^2, whose square root is computed coefficientwise with fq_sqrt. Otherwise the valuation must be even, the constant term must be a square in \mathbb{F}_q, and the candidate square root is computed as a power series square root of length len / 2 + 1 and checked by squaring its high part.
Cite this page
The FLINT team, “_fq_poly_sqrt, fq_poly_sqrt (fq_poly.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/fq_poly/_fq_poly_sqrt.html (generated 2026-10-20).
@misc{flint-doc-fq-poly-fq-poly-sqrt,
author = {{The FLINT team}},
title = {{\_fq\_poly\_sqrt, fq\_poly\_sqrt (fq\_poly.h)}},
howpublished = {FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev},
year = {2026},
url = {https://flintlib.org/doc/fq_poly/_fq_poly_sqrt.html},
note = {Generated 2026-10-20}
}