Class: When::Ephemeris::Formula

Inherits:
BasicTypes::Object show all
Includes:
When::Ephemeris, Parts::MethodCash
Defined in:
lib/when_exe/ephemeris.rb

Overview

暦法オブジェクトに天体暦機能を提供する

Direct Known Subclasses

Hindu, MeanLunation

Defined Under Namespace

Modules: ForwardedFormula

Constant Summary collapse

CYCLE_0M =

Seed

0
CYCLE_1M = 
1000000
Sgn =

Year Event

[[-1,+1],[-1,-1],[+1,-1],[+1,+1]]
Bs = 
[[11.0,  7.0, 11.0,  7.0],
[11.0,  7.0, 11.0,  7.0],
[11.0,  7.0, 11.0,  7.0],
[14.0,  8.5, 14.0,  8.5],
[16.0, 10.0, 16.0, 10.0],
[17.0, 14.0, 17.0, 14.0],
[17.0, 17.0, 17.0, 17.0]]

Constants included from When::Ephemeris

AU, AcS, BCENT, C0, CIRCLE, COS, COSL, COSLT, COST, DAY, DEG, EPOCH1800, EPOCH1900, EPOCH1975, EPOCH2000, FARAWAY, JCENT, JYEAR, Jupiter, LIN, Mars, Mercury, Neptune, P0B, P0L, P0P, P0dB, P0dL, P1B, P1L, P1R, P2B, P2L, P2Q, P2dL, P3L, P3Q, P4B, P4L, P4Q, P4dL, P5B, P5L, P5Q, P5dL, P5l, P5n, P5r, P5t, P6B, P6L, P6Q, P6dL, P6l, P6n, P6r, P6t, P7B, P7L, P7R, P8B, P8L, P8R, P9B, P9L, P9R, PSEC, Pluto, SIN, SINL, SINLT, SINT, Saturn, Uranus, Venus

Constants included from Parts::MethodCash

Parts::MethodCash::Escape

Constants included from Parts::Resource

Parts::Resource::ConstList, Parts::Resource::ConstTypes, Parts::Resource::IRIHeader, Parts::Resource::LabelProperty

Instance Attribute Summary collapse

Attributes inherited from BasicTypes::Object

#label

Attributes included from Parts::Resource

#_pool, #child, #keys, #locale, #namespace

Instance Method Summary collapse

Methods included from When::Ephemeris

_adjust, _rot, _to_p2, _to_p3, _to_r3, acos, asin, cosc, cosd, delta_e, delta_p, julian_century_from_2000, julian_year_from_1975, obl, polynomial, root, sinc, sind, tanc, tand, trigonometric

Methods included from Parts::MethodCash

_setup_, _setup_info, escape, #method_missing, #method_missing_

Methods included from Parts::Resource

#[], #^, _abbreviation_to_iri, _decode, _encode, _extract_prefix, _instance, _instantiate, _parse, _path_with_prefix, _replace_tags, _setup_, _setup_info, _simplify_path, base_uri, #each, #enum_for, #hierarchy, #include?, #included?, #iri, #leaf?, #m17n, #map, #next, #parent, #prev, #registered?, root_dir

Methods included from Parts::Resource::Pool

#[], #[]=, #_pool, #_setup_, #pool_keys

Methods included from Parts::Resource::Synchronize

#synchronize

Dynamic Method Handling

This class handles dynamic methods through the method_missing method in the class When::Parts::MethodCash

Instance Attribute Details

#alt ⇒ Numeric (readonly)

観測地の高度 / m

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1186

def alt
  @alt
end

#formula ⇒ String, Hash (readonly)

計算対象 - 公式の指定

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1170

def formula
  @formula
end

#graha ⇒ Hash<Symbol=>When::Ephemeris::Datum> (readonly)

天体オブジェクトを保持するハッシュ

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1198

def graha
  @graha
end

#is_dynamical ⇒ Boolean (readonly)

時刻系が dynamical か

Returns:

  • (Boolean) 


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# File 'lib/when_exe/ephemeris.rb', line 1194

def is_dynamical
  @is_dynamical
end

#lat ⇒ Numeric (readonly)

観測地の基準緯度 / 度

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1182

def lat
  @lat
end

#location ⇒ When::Coordinates::Spatial (readonly)

観測地

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1174

def location
  @location
end

#long ⇒ Numeric (readonly)

観測地の基準経度 / 度

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1178

def long
  @long
end

#time_standard ⇒ String (readonly)

時刻系(‘universal’ or ‘dynamical’)

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1190

def time_standard
  @time_standard
end

Instance Method Details

#_coords(t, system, target) ⇒ When::Ephemeris::Coords

天体の位置情報

Parameters:

  • t (Numeric) —

    ユリウス日(Terrestrial Time)

  • t (When::TM::TemporalPosition)
  • system (Integer) —

    座標系

    0 - 黄道座標 When::Coordinates::Spatial::ECLIPTIC
    1 - 赤道座標 When::Coordinates::Spatial::EQUATORIAL
    2 - 赤道座標[時角

    When::Coordinates::Spatial::EQUATORIAL_HA ]

    3 - 地平座標 When::Coordinates::Spatial::HORIZONTAL
  • target (When::Ephemeris::CelestialObject) —

    対象星

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1283

def _coords(t, system, target)
  pos = target.coords(t, @location)
  pos = pos.y_to_r(t, @location)  if system >= When::Coordinates::Spatial::EQUATORIAL
  pos = pos.r_to_rh(t, @location) if system >= When::Coordinates::Spatial::EQUATORIAL_HA
  pos = pos.rh_to_h(t, @location) if system >= When::Coordinates::Spatial::HORIZONTAL
  return pos
end

#_to_seed_type(d, seed) ⇒ Numeric, When::TM::TemporalPosotion

ユリウス日(Numeric)を seed と同じ型に変換して返します。

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) 


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# File 'lib/when_exe/ephemeris.rb', line 1538

def _to_seed_type(d, seed)
  case seed
  when Numeric         ; return d
  when When::TimeValue ; seed = seed._attr
  else                 ; seed = seed.dup
  end
  seed[:precision] = nil
  seed[:clock]   ||= When::TM::Clock.local_time
  t = When::TM::JulianDate._d_to_t(d)
  seed[:frame].jul_trans(@is_dynamical ? When::TM::JulianDate.dynamical_time(t) :
                                         When::TM::JulianDate.universal_time(t), seed)
end

#cn_to_time_(cn, time0 = nil) ⇒ Numeric

周期番号 -> 日時

Parameters:

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1233

def cn_to_time_(cn, time0=nil)
  time0 ||= (cn - @cycle_number_0m) / @cycle_number_1m
  root(time0, cn) {|t| time_to_cn(t)}
end

#day_event(t, event, target = When.Resource('_ep:Sun'), height = nil) ⇒ Numeric, When::TM::TemporalPosotion

天体の出没最大高度日時

Parameters:

  • t (Numeric) —

    ユリウス日(Terrestrial Time)

  • t (When::TM::TemporalPosition)
  • event (Integer) —
    -1 - 出
    0 - 南中
    +1 - 没
    nil - 最大高度
  • target (When::Ephemeris::CelestialObject) (defaults to: When.Resource('_ep:Sun')) —

    対象星(デフォルトは太陽)

  • height (Numeric) (defaults to: nil) —

    閾値高度/度

  • height (String) (defaults to: nil) —
    ‘0’ - 太陽の上端が地平線(大気差考慮) - 太陽のデフォルト
    ‘A’ - 天体の中心が地平線(大気差考慮) - 太陽以外のデフォルト
    ‘T’ - 夜明け/日暮れ

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    計算結果

    t が ユリウス日(Terrestrial Time) => ユリウス日(Terrestrial Time)
    t が その他 => When::TM::DateAndTime 


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# File 'lib/when_exe/ephemeris.rb', line 1341

def day_event(t, event, target=When.Resource('_ep:Sun'), height=nil)
  # 時刻の初期値
  dl  = @location.long / (360.0 * When::Coordinates::Spatial::DEGREE)
  t0  = (+t + dl).round - dl
  dt  = _coords(t0, When::Coordinates::Spatial::EQUATORIAL, target).phi -
        @location.local_sidereal_time(t0) / 24.0 + 0.25 * (event||0)
  t0 += dt - dt.round

  # 天体の地平座標での高度または方位角
  case event
  when 0
    meridian = _coords(t0, When::Coordinates::Spatial::EQUATORIAL_HA, target).phi.round
  when +1, -1
    height ||= target.instance_of?(When::Ephemeris::Sun) ? '0' : 'A'
    if height.kind_of?(String)
      height = @location.datum.zeros[height.upcase]
      raise ArgumentError, 'invalid height string' unless height
    end
    height = height / 360.0 - (0.25 - @location.horizon) +
           [@location.alt / (1000.0 * @location.datum.air[0]), 1].min * @location.datum.zeros['A'] / 360.0
  else
    height = nil # 極値検索のため
  end

  # イベントの時刻
  _to_seed_type(
    event == 0 ? (root(t0, meridian, 1) {|t1| _coords(t1, When::Coordinates::Spatial::EQUATORIAL_HA, target).phi}) :
                 (root(t0, height     ) {|t1| _coords(t1, When::Coordinates::Spatial::HORIZONTAL, target).theta }),
   t)
rescue RangeError
  nil
end

#meridian_passage_of_moon(t) ⇒ Numeric, When::TM::TemporalPosotion

月の南中の日時

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    月の南中の日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime 該当時刻がなければ nil



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# File 'lib/when_exe/ephemeris.rb', line 1476

def meridian_passage_of_moon(t)
  day_event_in_the_day(t, 0, When.Resource('_ep:Moon'))
end

#meridian_passage_of_sun(t) ⇒ Numeric, When::TM::TemporalPosotion

太陽の南中の日時

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    太陽の南中の日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime



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# File 'lib/when_exe/ephemeris.rb', line 1422

def meridian_passage_of_sun(t)
  day_event(t, 0, When.Resource('_ep:Sun'))
end

#moon_noon(t) ⇒ Numeric, When::TM::TemporalPosotion

月の最大高度の日時

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    月の最大高度の日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime 該当時刻がなければ nil



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# File 'lib/when_exe/ephemeris.rb', line 1464

def moon_noon(t)
  day_event_in_the_day(t, nil, When.Resource('_ep:Moon'))
end

#moon_visibility(t) ⇒ Numeric

Note:

満月に近い場合は考慮されていません。主に新月の初見の確認に用います。

日没時に月が見えるか否か

Parameters:

Returns:

  • (Numeric) —
    正 - 見える
    負 - 見えない 


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# File 'lib/when_exe/ephemeris.rb', line 1302

def moon_visibility(t)
  sun  = When.Resource('_ep:Sun')
  moon = When.Resource('_ep:Moon')

  # 日没時刻
  t = day_event(+t, +1, sun, 'Z')

  # 月の地平線からの高度
  h = _coords(t, When::Coordinates::Spatial::HORIZONTAL, moon).theta * 360.0

  # 月と太陽の離角
  p = moon.elongation(t, sun, @location) * 360.0

  # 指標の計算
  n = 4.0 - 0.1*p
  f = p < 40.0 ? 4.0 + n*(n+1)/2 : 4.0
  return (h / f - 1.0)
end

#moonrise(t, height = 'A') ⇒ Numeric, When::TM::TemporalPosotion

月の出の日時

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    月の出の日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime 該当時刻がなければ nil



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# File 'lib/when_exe/ephemeris.rb', line 1437

def moonrise(t, height='A')
  day_event_in_the_day(t, -1, When.Resource('_ep:Moon'), height)
end

#moonset(t, height = 'A') ⇒ Numeric, When::TM::TemporalPosotion

月の入りの日時

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    月の入りの日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime 該当時刻がなければ nil



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# File 'lib/when_exe/ephemeris.rb', line 1452

def moonset(t, height='A')
  day_event_in_the_day(t, +1, When.Resource('_ep:Moon'), height)
end

#nearest_past(date, n = 0, d = 1) ⇒ Numeric, When::TM::TemporalPosition

指定の周期番号パターンになる最も近い過去の日時

Parameters:

  • date (Numeric) —

    ユリウス日(Terrestrial Time)

  • date (When::TM::TemporalPosition)
  • n (Numeric) (defaults to: 0) —

    相対周期番号(n=0 なら date または date の直前が基準)

  • d (Numeric) (defaults to: 1) —

    単位周期数

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1260

def nearest_past(date, n=0, d=1)
  i, f = n.divmod(d)
  t0   = @is_dynamical ? +date : date.to_f
  cn   = time_to_cn(date).divmod(d)[0] * d + f
  cn  -= d while (t1 = cn_to_time(cn)) > t0
  _to_seed_type((i == 0) ? t1 : cn_to_time(cn+i*d), date)
end

#phase_range(date) ⇒ Array<Numeric>

当該日付の月の位相の変化範囲

Parameters:

Returns:

  • (Array<Numeric>) —

    当該日付の月の位相の変化範囲



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# File 'lib/when_exe/ephemeris.rb', line 1244

def phase_range(date)
  date = date.floor
  [date, date.succ].map {|d|
    time_to_cn(d)
  }
end

#sun_noon(t) ⇒ Numeric, When::TM::TemporalPosotion

太陽の最大高度の日時

Parameters:

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    太陽の最大高度の日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime



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# File 'lib/when_exe/ephemeris.rb', line 1411

def sun_noon(t)
  day_event(t, nil, When.Resource('_ep:Sun'))
end

#sunrise(t, height = '0') ⇒ Numeric, When::TM::TemporalPosotion

日の出の日時

Parameters:

  • t (Numeric) —

    ユリウス日(Terrestrial Time)

  • t (When::TM::TemporalPosition)
  • height (Numeric) (defaults to: '0') —

    閾値高度/度

  • height (String) (defaults to: '0') —
    ‘0’ - 太陽の上端が地平線(大気差考慮) - 太陽のデフォルト
    ‘T’ - 夜明け

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    日の出の日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime



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# File 'lib/when_exe/ephemeris.rb', line 1385

def sunrise(t, height='0')
  day_event(t, -1, When.Resource('_ep:Sun'), height)
end

#sunset(t, height = '0') ⇒ Numeric, When::TM::TemporalPosotion

日の入りの日時

Parameters:

  • t (Numeric) —

    ユリウス日(Terrestrial Time)

  • t (When::TM::TemporalPosition)
  • height (Numeric) (defaults to: '0') —

    閾値高度/度

  • height (String) (defaults to: '0') —
    ‘0’ - 太陽の上端が地平線(大気差考慮) - 太陽のデフォルト
    ‘T’ - 日暮れ

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    日の入りの日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime



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# File 'lib/when_exe/ephemeris.rb', line 1400

def sunset(t, height='0')
  day_event(t, +1, When.Resource('_ep:Sun'), height)
end

#time_to_cn(t) ⇒ Numeric

日時 -> 周期番号

Parameters:

Returns:



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# File 'lib/when_exe/ephemeris.rb', line 1223

def time_to_cn(t)
  @proc.call(t)
end

#year_event(t, event, target, hs = , bs = nil) ⇒ Numeric, When::TM::TemporalPosotion

恒星の出没と太陽の位置関係に関するイベントの日時

Parameters:

  • t (Numeric) —

    ユリウス日(Terrestrial Time)

  • t (When::TM::TemporalPosition)
  • event (Integer) —
    0 - first visible rising (=ヘリアカル・ライジング)
    1 - last visible rising
    2 - last visible setting
    3 - first visible setting
  • target (When::Ephemeris::CelestialObject) —

    対象の恒星

  • hs (Numeric) (defaults to: ) —

    恒星の高度/度(地平線上が正)

  • bs (Numeric) (defaults to: nil) —

    太陽の伏角/度(地平線上が負, よって通常は正です, デフォルトは Bs表引き)

Returns:

  • (Numeric, When::TM::TemporalPosotion) —

    イベントの日時(ユリウス日(Terrestrial Time)またはWhen::TM::DateAndTime



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# File 'lib/when_exe/ephemeris.rb', line 1495

def year_event(t, event, target, hs= @location.datum.zeros['A'], bs=nil)
  # difference of ecliptic longitude between zenith and target star 
  # when the event happens
  pos  = _coords(+t, When::Coordinates::Spatial::EQUATORIAL, target)
  long = @location.long / When::Coordinates::Spatial::DEGREE
  lat  = @location.lat  / When::Coordinates::Spatial::DEGREE
  dp   = (sind(hs) - sind(lat) * sinc(pos.theta)) / 
                    (cosd(lat) * cosc(pos.theta))

  return nil if dp.abs >= 1
  dp  = acos(dp) / CIRCLE

  # The Sun's height when the event happens
  unless bs
    mag = target.luminosity
    bs  = Bs[mag<-0.5 ?  0 : (mag<4.5 ? mag.round+1 : 6)][event]
  end

  # イベントの時刻
  zenith = Coords.polar(pos.phi+Sgn[event][0]*dp, lat/360.0).r_to_y(+t, @location)
  s   = sind(bs)/cosc(zenith.theta)
  arc = asin(s) / CIRCLE + 0.25
  lam = _true_sun(+t).floor+(zenith.phi+Sgn[event][1]*arc).divmod(1)[1]
  tt  = nil
  loop do
    tt = root(+t, lam) {|t1| _true_sun(t1)}
    break if tt >= +t
    lam += 1
  end
  _to_seed_type(day_event((tt+long/360.0).round, Sgn[event][0], When.Resource('_ep:Sun'), bs), t)
rescue RangeError
  nil
end