Classes
struct	BodyLocal
	A body's local hour angle and equatorial position at one instant. More...
struct	AltitudeExtremum
	A refined local extremum of the altitude curve: its instant, kind, and value. More...
struct	Solved
	A refined crossing and the \|altitude − h₀\| residual it left, in degrees. More...
struct	DayWindow
	The TT endpoints of one half-open UT1 calendar day. More...

Typedefs
using	AltitudeGrid

Functions
auto	validate (const GeoLocation &location) -> void
	Validate an observer location, throwing on out-of-range or non-finite coordinates.
auto	jde_tt_to_jd_ut1 (const double jde_tt) -> double
	Convert a JDE (TT) to the JD (UT1) of the same instant.
template<BodyProvider P>
auto	body_local (const double jde_tt, const GeoLocation &location, const P &provider) -> BodyLocal
	Compute a body's local hour angle and equatorial coordinates for an observer.
template<BodyProvider P>
auto	altitude (const double jde_tt, const GeoLocation &location, const P &provider) -> toolbox::AngleDeg
	Compute a body's geometric altitude for an observer at one instant.
template<typename Func> requires std::invocable<const Func&, double> and std::convertible_to<std::invoke_result_t<const Func&, double>, double>
auto	golden_section_argmin (const Func &f, const double a, const double b, const double tolerance=EXTREMUM_SEARCH_TOLERANCE_DAYS) -> double
	Find the argmin of a unimodal function on [a, b] by golden-section search.
template<typename Func>
auto	altitude_grid (const Func &f, const double start_jde_tt, const double step_days) -> AltitudeGrid
	Sample every grid endpoint in increasing TT order, including both window ends.
template<typename Func>
auto	interior_extrema (const Func &f, const double start_jde_tt, const double step_days, const AltitudeGrid &values) -> std::vector< AltitudeExtremum >
	Refine strict direction changes; a flat plateau does not define an interior extremum.
template<typename Func>
auto	append_edge_extrema (const Func &f, const double lo_jde_tt, const double hi_jde_tt, std::vector< AltitudeExtremum > &extrema) -> void
	Probe a cell with a missing outer grid neighbor for an interior minimum and maximum.
template<typename Func> requires std::invocable<const Func&, double> and std::convertible_to<std::invoke_result_t<const Func&, double>, double>
auto	find_extrema (const Func &f, const double a, const double b) -> std::vector< AltitudeExtremum >
	Find every local extremum of the altitude curve on [a, b], in time order.
template<BodyProvider P>
auto	min_altitude_jde (const double transit, const bool before, const GeoLocation &location, const P &provider) -> double
	Find the instant of minimum altitude in the half-arc adjacent to a transit.
auto	validate_pm90 (const char *name, const double angle_deg) -> void
	Reject a named non-finite angle or one outside [-90°, 90°].
auto	validate_rise_set_inputs (const double transit_jde_tt, const GeoLocation &location, const toolbox::AngleDeg &h0) -> void
	Validate rise_set_jde's inputs.
template<typename Func> requires std::invocable<const Func&, double> and std::convertible_to<std::invoke_result_t<const Func&, double>, double>
auto	crossing_in_bracket (const Func &f, const double lo_jde, const double hi_jde, const bool rising) -> std::optional< Solved >
	Try to solve one altitude crossing inside a bracket.
template<BodyProvider P>
auto	polish_transit (const double estimate_jde, const GeoLocation &location, const P &provider) -> double
	Polish a transit estimate into the instant of upper culmination (H = 0).
auto	day_window (const std::chrono::year_month_day &ymd_ut1) -> DayWindow
	Convert both UT1 midnights independently; a UT1 day is not exactly one TT day.
auto	crossing_error (const std::string_view caller, const bool rising, const Solved &solved, const double lo_jde_tt, const double hi_jde_tt) -> std::runtime_error
	Describe a bracketed altitude crossing that failed its caller's residual guard.
template<typename Func>
auto	scan_day_crossings (const Func &f, const DayWindow &window, const std::vector< AltitudeExtremum > &extrema, Result &result) -> void
	Scan monotone segments in time order, trying rise before set and keeping later crossings.
template<typename Func>
auto	day_polar (const Func &h, const DayWindow &window, const std::vector< AltitudeExtremum > &extrema, const toolbox::AngleDeg &h0) -> Polar
	Classify a crossing-free day from its global altitude bounds, including the window ends.

Variables
constexpr std::size_t	EXTREMUM_SCAN_CELLS

Typedef Documentation

◆ AltitudeGrid

using astro::rise_set::detail::AltitudeGrid

Function Documentation

◆ altitude()

template<BodyProvider P>

auto astro::rise_set::detail::altitude	(	const double	jde_tt,
		const GeoLocation &	location,
		const P &	provider )->toolbox::AngleDeg

inlinenodiscard

Compute a body's geometric altitude for an observer at one instant.

Parameters

jde_tt	The instant, as a julian ephemeris day on the TT scale.
location	The observer's location.
provider	The body's position provider.

Returns: The body's altitude, in [-90°, 90°]. Purely geometric — refraction enters only through the h₀ convention, not through this function.

◆ altitude_grid()

template<typename Func>

auto astro::rise_set::detail::altitude_grid	(	const Func &	f,
		const double	start_jde_tt,
		const double	step_days )->AltitudeGrid

inlinenodiscard

Sample every grid endpoint in increasing TT order, including both window ends.

◆ append_edge_extrema()

template<typename Func>

auto astro::rise_set::detail::append_edge_extrema	(	const Func &	f,
		const double	lo_jde_tt,
		const double	hi_jde_tt,
		std::vector< AltitudeExtremum > &	extrema )->void

inline

Probe a cell with a missing outer grid neighbor for an interior minimum and maximum.

Note: A candidate must beat both endpoints. Only same-kind extrema within the endpoint exclusion distance count as duplicates; distinct extrema may share a cell.

◆ body_local()

template<BodyProvider P>

auto astro::rise_set::detail::body_local	(	const double	jde_tt,
		const GeoLocation &	location,
		const P &	provider )->BodyLocal

inlinenodiscard

Compute a body's local hour angle and equatorial coordinates for an observer.

Parameters

jde_tt	The instant, as a julian ephemeris day on the TT scale.
location	The observer's location.
provider	The body's position provider.

Returns: The hour angle (unwrapped to [-180°, 180°)) and the equatorial coordinates.

Note: The sidereal time is evaluated on the UT1 scale (pitfall: feeding TT would shift the result by ΔT ≈ 69 s); the body's position and the nutation terms are evaluated on TT.

◆ crossing_error()

auto astro::rise_set::detail::crossing_error	(	const std::string_view	caller,
		const bool	rising,
		const Solved &	solved,
		const double	lo_jde_tt,
		const double	hi_jde_tt )->std::runtime_error

inlinenodiscard

Describe a bracketed altitude crossing that failed its caller's residual guard.

◆ crossing_in_bracket()

template<typename Func>
requires std::invocable<const Func&, double> and std::convertible_to<std::invoke_result_t<const Func&, double>, double>

auto astro::rise_set::detail::crossing_in_bracket	(	const Func &	f,
		const double	lo_jde,
		const double	hi_jde,
		const bool	rising )->std::optional< Solved >

inlinenodiscard

Try to solve one altitude crossing inside a bracket.

Parameters

f	The residual function (altitude − h₀), in degrees, over JDE (TT).
lo_jde	The left bracket end, inclusive.
hi_jde	The right bracket end, exclusive.
rising	True for an upward crossing (rise side), false for a downward one.

Returns: nullopt when the bracket ends do not straddle a crossing in the required direction (a plain sign change is not enough — direction is what rejects event-free brackets); otherwise the refined root plus its residual. The residual verdict is the caller's: a straddle proves a root exists, so what a rejection means depends on the bracket.

◆ day_polar()

template<typename Func>

auto astro::rise_set::detail::day_polar	(	const Func &	h,
		const DayWindow &	window,
		const std::vector< AltitudeExtremum > &	extrema,
		const toolbox::AngleDeg &	h0 )->Polar

inlinenodiscard

Classify a crossing-free day from its global altitude bounds, including the window ends.

Exceptions

std::runtime_error If the bounds straddle h₀ despite the absence of a solved crossing.

◆ day_window()

auto astro::rise_set::detail::day_window ( const std::chrono::year_month_day & ymd_ut1 ) ->DayWindow

inlinenodiscard

Convert both UT1 midnights independently; a UT1 day is not exactly one TT day.

Note: Adding 86400 TT seconds would leave gaps or overlaps as ΔT changes between adjacent dates.

◆ find_extrema()

template<typename Func>
requires std::invocable<const Func&, double> and std::convertible_to<std::invoke_result_t<const Func&, double>, double>

auto astro::rise_set::detail::find_extrema	(	const Func &	f,
		const double	a,
		const double	b )->std::vector< AltitudeExtremum >

inlinenodiscard

Find every local extremum of the altitude curve on [a, b], in time order.

Note: Grid scan for direction changes (15-min cells on a 1-day window) plus a direct probe of each edge cell, then golden-section refinement per candidate. The window must be partitioned at ALL of these, not just at the global minimum and maximum: the global extremum need not be a monotone cut (2026-06-18 Tromsø: the window's end dips below the interior minimum, and partitioning at the global minimum hid that day's only rise inside a non-monotone segment — pinned by a golden row).

◆ golden_section_argmin()

template<typename Func>
requires std::invocable<const Func&, double> and std::convertible_to<std::invoke_result_t<const Func&, double>, double>

auto astro::rise_set::detail::golden_section_argmin	(	const Func &	f,
		const double	a,
		const double	b,
		const double	tolerance = EXTREMUM_SEARCH_TOLERANCE_DAYS )->double

inlinenodiscard

Find the argmin of a unimodal function on [a, b] by golden-section search.

Note: Derivative-free; a monotone objective contracts toward an endpoint, as on polar-boundary arcs.; At |JDE| >= 2²³ the double ULP exceeds the default tolerance, so contraction can stall. The 64-update cap still terminates and returns (lower + upper) / 2 for the final bracket.

◆ interior_extrema()

template<typename Func>

auto astro::rise_set::detail::interior_extrema	(	const Func &	f,
		const double	start_jde_tt,
		const double	step_days,
		const AltitudeGrid &	values )->std::vector< AltitudeExtremum >

inlinenodiscard

Refine strict direction changes; a flat plateau does not define an interior extremum.

◆ jde_tt_to_jd_ut1()

auto astro::rise_set::detail::jde_tt_to_jd_ut1 ( const double jde_tt ) ->double

inlinenodiscard

Convert a JDE (TT) to the JD (UT1) of the same instant.

Parameters

jde_tt The julian ephemeris day, on the TT scale.

Returns: The julian day number, on the UT1 scale.

◆ min_altitude_jde()

template<BodyProvider P>

auto astro::rise_set::detail::min_altitude_jde	(	const double	transit,
		const bool	before,
		const GeoLocation &	location,
		const P &	provider )->double

inlinenodiscard

Find the instant of minimum altitude in the half-arc adjacent to a transit.

Parameters

transit	The upper-culmination instant (JDE, TT scale).
before	True for the half-arc preceding the transit, false for the following one.
location	The observer's location.
provider	The body's position provider.

Returns: The argmin instant (JDE, TT scale).

Note: Golden-section search around the nominal lower culmination — NOT a solve of H = ±180°. With dδ/dt ≠ 0 the true altitude minimum wanders off the lower culmination (for the Moon, degrees of hour angle); the existence check must anchor on the true minimum, or grazing days fall into a blind band and read as polar (#62).

◆ polish_transit()

template<BodyProvider P>

auto astro::rise_set::detail::polish_transit	(	const double	estimate_jde,
		const GeoLocation &	location,
		const P &	provider )->double

inlinenodiscard

Polish a transit estimate into the instant of upper culmination (H = 0).

Parameters

estimate_jde	The estimated transit instant, as a julian ephemeris day on the TT scale. Must lie within TRANSIT_BRACKET_HALF_WIDTH_DAYS of the true transit.
location	The observer's location.
provider	The body's position provider.

Returns: The transit instant (JDE, TT scale).

Exceptions

std::invalid_argument If location is out of range.

Note: The root of H = 0 is found with toolbox::newton_method on the unwrapped hour angle.

◆ scan_day_crossings()

template<typename Func>

auto astro::rise_set::detail::scan_day_crossings	(	const Func &	f,
		const DayWindow &	window,
		const std::vector< AltitudeExtremum > &	extrema,
		Result &	result )->void

inline

Scan monotone segments in time order, trying rise before set and keeping later crossings.

Note: Extrema must already be sorted. Residual rejection here uses > guard; the transit-centered fallback accepts with <= guard, which rejects NaN where this scan retains it.

◆ validate()

auto astro::rise_set::detail::validate ( const GeoLocation & location ) ->void

inline

Validate an observer location, throwing on out-of-range or non-finite coordinates.

Parameters

location The location to validate.

Exceptions

std::invalid_argument If latitude ∉ [-90°, 90°] or longitude ∉ [-180°, 180°], or either is not finite.

◆ validate_pm90()

auto astro::rise_set::detail::validate_pm90	(	const char *	name,
		const double	angle_deg )->void

inline

Reject a named non-finite angle or one outside [-90°, 90°].

◆ validate_rise_set_inputs()

auto astro::rise_set::detail::validate_rise_set_inputs	(	const double	transit_jde_tt,
		const GeoLocation &	location,
		const toolbox::AngleDeg &	h0 )->void

inline

Validate rise_set_jde's inputs.

Exceptions

std::invalid_argument If transit_jde_tt is not finite, location is out of range, or h0 is not finite or outside [-90°, 90°].

Variable Documentation

◆ EXTREMUM_SCAN_CELLS

std::size_t astro::rise_set::detail::EXTREMUM_SCAN_CELLS

inlineconstexpr

Classes

Typedefs

Functions

Variables

Typedef Documentation

◆ AltitudeGrid

Function Documentation

◆ altitude()

◆ altitude_grid()

◆ append_edge_extrema()

◆ body_local()

◆ crossing_error()

◆ crossing_in_bracket()

◆ day_polar()

◆ day_window()

◆ find_extrema()

◆ golden_section_argmin()

◆ interior_extrema()

◆ jde_tt_to_jd_ut1()

◆ min_altitude_jde()

◆ polish_transit()

◆ scan_day_crossings()

◆ validate()

◆ validate_pm90()

◆ validate_rise_set_inputs()

Variable Documentation

◆ EXTREMUM_SCAN_CELLS