Module: Sekki24::Lunar::PhaseFinder

Defined in:
lib/sekki24/lunar/phase_finder.rb

Constant Summary collapse

MEAN_NEW_MOON_EPOCH = 
2_451_550.09765
SYNODIC_MONTH = 
29.530588853
DERIVATIVE_HALF_WINDOW = 
1.0 / 24.0
ANGULAR_TOLERANCE = 
1e-7
NEWTON_ATTEMPTS = 
8

Class Method Summary collapse

Class Method Details

.clear_cache! ⇒ Object 



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# File 'lib/sekki24/lunar/phase_finder.rb', line 54

def clear_cache!
  @cache_mutex.synchronize do
    @root_cache.clear
    @year_cache.clear
  end
end

.new_moon_after(time) ⇒ Object

Raises:

  • (TypeError) 


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# File 'lib/sekki24/lunar/phase_finder.rb', line 45

def new_moon_after(time)
  raise TypeError, "expected Time, got #{time.class}" unless time.is_a?(Time)

  jde = TimeScale.utc_to_jde(time)
  lunation = ((jde - MEAN_NEW_MOON_EPOCH) / SYNODIC_MONTH).ceil
  root = root_for(lunation)
  root <= time ? root_for(lunation + 1) : root
end

.new_moon_before(time) ⇒ Object

Raises:

  • (TypeError) 


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# File 'lib/sekki24/lunar/phase_finder.rb', line 36

def new_moon_before(time)
  raise TypeError, "expected Time, got #{time.class}" unless time.is_a?(Time)

  jde = TimeScale.utc_to_jde(time)
  lunation = ((jde - MEAN_NEW_MOON_EPOCH) / SYNODIC_MONTH).floor
  root = root_for(lunation)
  root > time ? root_for(lunation - 1) : root
end

.new_moons(year, tz:) ⇒ Object 



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# File 'lib/sekki24/lunar/phase_finder.rb', line 19

def new_moons(year, tz:)
  calendar_year = validate_year(year)
  new_moons_for_calendar(calendar_year, tz: tz)
end

.new_moons_for_calendar(calendar_year, tz:) ⇒ Object 



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# File 'lib/sekki24/lunar/phase_finder.rb', line 24

def new_moons_for_calendar(calendar_year, tz:)
  cache_key = [calendar_year, TimeScale.timezone_key(tz)].freeze
  cached = @cache_mutex.synchronize { @year_cache[cache_key] }
  return cached if cached

  roots = roots_near_year(calendar_year).filter_map do |time|
    local = TimeScale.localize(time, tz)
    local.freeze if local.year == calendar_year
  end.freeze
  @cache_mutex.synchronize { @year_cache[cache_key] ||= roots }
end