class Date

Public Class Methods

easter(y, sg=ITALY)

Alias for: gregorian_easter

gregorian_easter(y, sg=ITALY) click to toggle source

# File lib/date/holiday.rb, line 268
def self.gregorian_easter(y, sg=ITALY)
  a = y % 19
  b, c = y.divmod(100)
  d, e = b.divmod(4)
  f = ((b + 8) / 25).to_i
  g = ((b - f + 1) / 3).to_i
  h = (19 * a + b - d - g + 15) % 30
  i, k = c.divmod(4)
  l = (32 + 2 * e + 2 * i - h - k) % 7
  m = ((a + 11 * h + 22 * l) / 451).to_i
  n, p = (h + l - 7 * m + 114).divmod(31)
  Date.new(y, n, p + 1, GREGORIAN).new_start(sg)
end

Also aliased as: easter

julian_easter(y, sg=ITALY) click to toggle source

# File lib/date/holiday.rb, line 258
def self.julian_easter(y, sg=ITALY)
  a = y % 4
  b = y % 7
  c = y % 19
  d = (19 * c + 15) % 30
  e = (2 * a + 4 * b - d + 34) % 7
  f, g = (d + e + 114).divmod(31)
  Date.new(y, f, g + 1, JULIAN).new_start(sg)
end

Public Instance Methods

easter?() click to toggle source

# File lib/date/holiday.rb, line 284
def easter?
  self ===
    (if julian?
       self.class.julian_easter(year)
     else
       self.class.gregorian_easter(year)
     end)
end

find_fdom(y, m, sg) click to toggle source

# File lib/date/holiday.rb, line 50
def find_fdom(y, m, sg)
  1.upto(31) do |d|
    if Date.valid_civil?(y, m, d, sg)
      return Date.new(y, m, d, sg).jd
    end
  end
end

find_ldom(y, m, sg) click to toggle source

# File lib/date/holiday.rb, line 58
def find_ldom(y, m, sg)
  31.downto(1) do |d|
    if Date.valid_civil?(y, m, d, sg)
      return Date.new(y, m, d, sg).jd
    end
  end
end

monday?() click to toggle source

# File lib/date/holiday.rb, line 164
def monday? () wday == 1 end

national_holiday?() click to toggle source

# File lib/date/holiday.rb, line 199
def national_holiday?
  d = if julian? then self.gregorian else self end
  d.instance_eval do nhol2? || nhol32? || nhol33? end
end

nth_kday_to_jd(y, m, n, k, sg=GREGORIAN) click to toggle source

# File lib/date/holiday.rb, line 66
def nth_kday_to_jd(y, m, n, k, sg=GREGORIAN)
  j = if n > 0
        find_fdom(y, m, sg) - 1
      else
        find_ldom(y, m, sg) + 7
      end
  (j - (((j - k) + 1) % 7)) + 7 * n
end

old_national_holiday?() click to toggle source

# File lib/date/holiday.rb, line 250
def old_national_holiday?
  d = if julian? then self.gregorian else self end
  d.instance_eval do
    qfixed? || qnholx? ||
      ((2407141..2432752) === jd && (qveq? || qaeq?))        # 1878-06-05/1948-07-19
  end
end

sunday?() click to toggle source

# File lib/date/holiday.rb, line 163
def sunday? () wday == 0 end

Protected Instance Methods

need_subs?() click to toggle source

# File lib/date/holiday.rb, line 169
def need_subs?
  nhol2? && (sunday? || (self - 1).need_subs?)
end

nhol2?() click to toggle source

# File lib/date/holiday.rb, line 160
def nhol2? () fixed? || float? || veq? || aeq? || extra? end

Private Instance Methods

_aeq(y) click to toggle source

# File lib/date/holiday.rb, line 126
def _aeq(y)
  case y
  when 1851..1899; a = 22.2588; b = 1983.0
  when 1900..1979; a = 23.2588; b = 1983.0
  when 1980..2099; a = 23.2488; b = 1980.0
  when 2100..2150; a = 24.2488; b = 1980.0
  else; raise ArgumentError, 'domain error'
  end
  Date.new(y, 9, _deq(a, b, y)).jd
end

_deq(a, b, y) click to toggle source

# File lib/date/holiday.rb, line 111
def _deq(a, b, y)
  (a + 0.242194 * (y - 1980) - ((y - b) / 4).to_i).to_i
end

_veq(y) click to toggle source

# File lib/date/holiday.rb, line 115
def _veq(y)
  case y
  when 1851..1899; a = 19.8277; b = 1983.0
  when 1900..1979; a = 20.8357; b = 1983.0
  when 1980..2099; a = 20.8431; b = 1980.0
  when 2100..2150; a = 21.8510; b = 1980.0
  else; raise ArgumentError, 'domain error'
  end
  Date.new(y, 3, _deq(a, b, y)).jd
end

aeq?() click to toggle source

# File lib/date/holiday.rb, line 144
def aeq?
  return false unless (2432753..2506696) === jd       # 1948-07-20/2150-12-31
  jd == _aeq(year)
end

extra?() click to toggle source

# File lib/date/holiday.rb, line 149
def extra?
  jd == 2436669 ||    # 1959-04-10 # 16
  jd == 2447582 ||    # 1989-02-24
  jd == 2448208 ||    # 1990-11-12
  jd == 2449148 ||    # 1993-06-09
  jd == 2458605 ||    # 2019-05-01
  jd == 2458779       # 2019-10-22
end

fixed?() click to toggle source

# File lib/date/holiday.rb, line 8
def fixed?
  return false unless jd >= 2432753   # 1948-07-20/PooD
  *x = mon, mday
  xi = case year
       when 2020; 10
       when 2021; 8
       else; 11
       end
  (x == [ 1,  1]) ||                  # --01-01
  (x == [ 1, 15]  &&                  # --01-15 (1948-07-20/1999-12-31)
   jd <= 2451544) ||
  (x == [ 2, 11]  &&                  # --02-11 (1966-12-09/PooD)
   jd >= 2439469) ||
  (x == [ 2, 23]  &&                  # --02-23 (2019-05-01/PooD)
   jd >= 2458605) ||
  (x == [ 4, 29]) ||                  # --04-29
  (x == [ 5,  3]) ||                  # --05-03
  (x == [ 5,  4]  &&                  # --05-04 (2007-01-01/PooD)
   jd >= 2454102) ||
  (x == [ 5,  5]) ||                  # --05-05
  (x == [ 7, 20]  &&                  # --07-20 (1996-01-01/2002-12-31)
   jd >= 2450084  &&
   jd <= 2452640) ||
  (x == [ 8, xi]  &&                  # --08-11 (2016-01-01/PooD) ex 2020-08-10
   jd >= 2457389) ||
  (x == [ 9, 15]  &&                  # --09-15 (1966-06-25/2002-12-31)
   jd >= 2439302  &&
   jd <= 2452640) ||
  (x == [10, 10]  &&                  # --10-10 (1966-06-25/1999-12-31)
   jd >= 2439302  &&
   jd <= 2451544) ||
  (x == [11,  3]) ||                  # --11-03
  (x == [11, 23]) ||                  # --11-23
  (x == [12, 23]  &&                  # --12-23 (1989-02-17/2019-04-30)
   jd >= 2447575  &&
   jd <= 2458604)
end

float?() click to toggle source

# File lib/date/holiday.rb, line 86
def float?
  if year == 2020
    return jd == 2458862 || # --01-13
           jd == 2459054 || # --07-23
           jd == 2459055 || # --07-24
           jd == 2459114    # --09-21
  end
  if year == 2021
    return jd == 2459226 || # --01-11
           jd == 2459418 || # --07-22
           jd == 2459419 || # --07-23
           jd == 2459478    # --09-20
  end
  (mon ==  1 && nth_kday?(2, 1) &&    # 2nd Mon, Jan (2000-01-01/PooD)
   jd >= 2451545) ||
  (mon ==  7 && nth_kday?(3, 1) &&    # 3nd Mon, Jul (2003-01-01/PooD)
   jd >= 2452641) ||
  (mon ==  9 && nth_kday?(3, 1) &&    # 3nd Mon, Sep (2003-01-01/PooD)
   jd >= 2452641) ||
  (mon == 10 && nth_kday?(2, 1) &&    # 2nd Mon, Oct (2000-01-01/PooD)
   jd >= 2451545)
end

nhol32?() click to toggle source

# File lib/date/holiday.rb, line 175
def nhol32?
  if jd >= 2441785
    if jd <= 2454101                                  # 1973-04-12/2006-12-31
      self.monday? && (self - 1).nhol2?
    else                                              # 2007-01-01/PooD
      !nhol2? && (self - 1).need_subs?
    end
  end
end

nhol33?() click to toggle source

# File lib/date/holiday.rb, line 185
def nhol33?
  if jd >= 2446427
    if jd <= 2454101                                  # 1985-12-27/2006-12-31
      !sunday? && !nhol32? &&
        (self - 1).nhol2? && (self + 1).nhol2?
    else                                              # 2007-01-01/PooD
      !nhol2? &&
        (self - 1).nhol2? && (self + 1).nhol2?
    end
  end
end

nth_kday?(n, k) click to toggle source

# File lib/date/holiday.rb, line 80
def nth_kday? (n, k)
  k == wday && jd === nth_kday_to_jd(year, mon, n, k, start)
end

qaeq?() click to toggle source

# File lib/date/holiday.rb, line 232
def qaeq?
  return false unless (2405163..2432752) === jd       # 1873-01-04/1948-07-19
  jd == _aeq(year)
end

qfixed?() click to toggle source

# File lib/date/holiday.rb, line 204
def qfixed?
  return false unless (2405163..2432752) === jd       # 1873-01-04/1948-07-19
  *x = mon, mday
  (x == [ 1,  3] && (2405446..2432752) === jd) ||     # 1873-10-14/1948-07-19
  (x == [ 1,  5] && (2405446..2432752) === jd) ||     # 1873-10-14/1948-07-19
  (x == [ 1, 29] && (2405143..2405224) === jd) ||     # 1872-12-15/1873-03-06
  (x == [ 1, 30] && (2405446..2419649) === jd) ||     # 1873-10-14/1912-09-03
  (x == [ 2, 11] && (2405225..2432752) === jd) ||     # 1873-03-07/1948-07-19
  (x == [ 4,  3] && (2405446..2432752) === jd) ||     # 1873-10-14/1948-07-19
  (x == [ 4, 29] && (2424943..2432752) === jd) ||     # 1927-03-03/1948-07-19
  (x == [ 7, 30] && (2419650..2424942) === jd) ||     # 1912-09-04/1927-03-02
  (x == [ 8, 31] && (2419650..2424942) === jd) ||     # 1912-09-04/1927-03-02
  (x == [ 9, 17] && (2405446..2407535) === jd) ||     # 1873-10-14/1879-07-04
  (x == [10, 17] && (2407536..2432752) === jd) ||     # 1879-07-05/1948-07-19
  (x == [10, 31] && (2419967..2424942) === jd) ||     # 1913-07-18/1927-03-02
  (x == [11,  3] && (2405163..2419649) === jd) ||     # 1873-01-04/1912-09-03
  (x == [11,  3] && (2424943..2432752) === jd) ||     # 1927-03-03/1948-07-19
  (x == [11, 23] && (2405446..2432752) === jd) ||     # 1873-10-14/1948-07-19
  (x == [12, 25] && (2424943..2432752) === jd)        # 1927-03-03/1948-07-19
end

qnholx?() click to toggle source

# File lib/date/holiday.rb, line 239
def qnholx?
  jd == 2420812 ||    # 1915-11-10 # 160
  jd == 2420816 ||    # 1915-11-14 # 160
  jd == 2420818 ||    # 1915-11-16 # 160
  jd == 2425561 ||    # 1928-11-10 # 226
  jd == 2425565 ||    # 1928-11-14 # 226
  jd == 2425567       # 1928-11-16 # 226
end

qveq?() click to toggle source

# File lib/date/holiday.rb, line 227
def qveq?
  return false unless (2405163..2432752) === jd       # 1873-01-04/1948-07-19
  jd == _veq(year)
end

veq?() click to toggle source

# File lib/date/holiday.rb, line 139
def veq?
  return false unless (2432753..2506696) === jd       # 1948-07-20/2150-12-31
  jd == _veq(year)
end