acb_hypgeom_2f1_choose
Synopsis
#include <flint/acb_hypgeom.h>Chooses the method for computing {}_2F_1 from the location of z: returns 0 for direct summation, 1 to 5 for the transformation with that index in acb_hypgeom_2f1_transform, or 6 for the corner case.
Direct summation is chosen if |z| \le 1/4, the Pfaff transformation if |z/(z-1)| \le 1/4, the smaller of the two if either is at most 3/4, and otherwise the transformation that minimizes the modulus of the new argument, if that modulus is at most 3/4; the remaining region, around \exp(\pm\pi i/3), is the corner case.
Cite this page
The FLINT team, “acb_hypgeom_2f1_choose (acb_hypgeom.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/acb_hypgeom/acb_hypgeom_2f1_choose.html (generated 2026-10-20).
@misc{flint-doc-acb-hypgeom-acb-hypgeom-2f1-choose,
author = {{The FLINT team}},
title = {{acb\_hypgeom\_2f1\_choose (acb\_hypgeom.h)}},
howpublished = {FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev},
year = {2026},
url = {https://flintlib.org/doc/acb_hypgeom/acb_hypgeom_2f1_choose.html},
note = {Generated 2026-10-20}
}