bertini::endgame::EndgameConfig Struct Reference

Configuration common to all endgames (sampling and final-approximation tolerances). More...

#include <config.hpp>

Public Types
using	T = NumErrorT
	The numeric (error) type.

Public Attributes
T	sample_point_refinement_factor = 1e-2
	Extra tolerance for refining sample points before computing the final approximation.
unsigned	num_sample_points = 3
	Number of sample points used per approximation.
T	min_track_time = T(1e-100)
	Smallest time the endgame will track to (the neighborhood radius).
mpq_rational	sample_factor {1, 2}
	Geometric factor between successive sample times (exact rational).
unsigned	max_num_refinements = 4
	Maximum Newton refinements when sharpening endgame sample points. A tracked sample is already on the path to tracking tolerance (~1e-6), and Newton doubles the correct digits per iteration, so 4 covers any realistic refinement target (6 -> 12 -> 24 -> 48 -> 96 digits); more is never legitimately needed. (The old default of 15 was a remnant of poorly scaled random coefficient draws, since fixed by seed-rooted derivation.).
T	final_tolerance = 1e-11
	The tolerance to which to compute the endpoint using the endgame.
bool	refine_when_increasing_precision = false
	When true, re-refine retained samples after the endgame migrates to higher precision (default false).
T	minimum_for_c_over_k_stabilization = T(3)/T(4)
	How closely successive c/k estimates must agree to count as settled, as a ratio of the smaller to the larger.
unsigned int	num_needed_for_stabilization = 3
	How many consecutive c/k estimates must agree before the path is called to be in the endgame operating zone.

Detailed Description

Configuration common to all endgames (sampling and final-approximation tolerances).

Member Typedef Documentation

T

using bertini::endgame::EndgameConfig::T = NumErrorT

The numeric (error) type.

Member Data Documentation

final_tolerance

T bertini::endgame::EndgameConfig::final_tolerance = 1e-11

The tolerance to which to compute the endpoint using the endgame.

max_num_refinements

unsigned bertini::endgame::EndgameConfig::max_num_refinements = 4

Maximum Newton refinements when sharpening endgame sample points. A tracked sample is already on the path to tracking tolerance (~1e-6), and Newton doubles the correct digits per iteration, so 4 covers any realistic refinement target (6 -> 12 -> 24 -> 48 -> 96 digits); more is never legitimately needed. (The old default of 15 was a remnant of poorly scaled random coefficient draws, since fixed by seed-rooted derivation.).

min_track_time

T bertini::endgame::EndgameConfig::min_track_time = T(1e-100)

Smallest time the endgame will track to (the neighborhood radius).

minimum_for_c_over_k_stabilization

T bertini::endgame::EndgameConfig::minimum_for_c_over_k_stabilization = T(3)/T(4)

How closely successive c/k estimates must agree to count as settled, as a ratio of the smaller to the larger.

num_needed_for_stabilization

unsigned int bertini::endgame::EndgameConfig::num_needed_for_stabilization = 3

How many consecutive c/k estimates must agree before the path is called to be in the endgame operating zone.

num_sample_points

unsigned bertini::endgame::EndgameConfig::num_sample_points = 3

Number of sample points used per approximation.

refine_when_increasing_precision

bool bertini::endgame::EndgameConfig::refine_when_increasing_precision = false

When true, re-refine retained samples after the endgame migrates to higher precision (default false).

sample_factor

mpq_rational bertini::endgame::EndgameConfig::sample_factor {1, 2}

Geometric factor between successive sample times (exact rational).

sample_point_refinement_factor

T bertini::endgame::EndgameConfig::sample_point_refinement_factor = 1e-2

Extra tolerance for refining sample points before computing the final approximation.