FLINT3.7.0-dev
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_mp_real_submul_bounded

Synopsis#include <flint/mp_real.h>
void _mp_real_submul_bounded(mp_real_t res, const mp_real_t a, const mp_real_t b, const mp_real_t c, slong E, slong n)source

Set res to a - bc, given that |a - bc| < B^E. Only the window of the product that reaches the result is computed, and the result is wrong if the bound does not hold.

This is the residual of a Newton or Taylor step, whose bound comes from the radius of the previous approximation. The sign of a - bc is read off the top limb of the product window, so the bound must be rigorous.

Guides#

Cite this page

The FLINT team, “_mp_real_submul_bounded (mp_real.h),” FLINT: Fast Library for Number Theory, documentation, version 3.7.0-dev, 2026. https://flintlib.org/doc/mp_real/_mp_real_submul_bounded.html (generated 2026-10-20).