Module: FatCore::Date

Included in:
Date
Defined in:
lib/fat_core/date.rb

Defined Under Namespace

Modules: ClassMethods

Federal Holidays and Workdays collapse

FED_DECREED_HOLIDAYS =

Holidays decreed by Presidential proclamation

[
  # Obama decree extra day before Christmas See
  # http://www.whitehouse.gov/the-press-office/2012/12/21
  ::Date.parse('2012-12-24'),
  # And Trump
  ::Date.parse('2018-12-24')
].freeze
PRESIDENTIAL_FUNERALS =

Presidential funeral since JFK

[
  # JKF Funeral
  ::Date.parse('1963-11-25'),
  # DWE Funeral
  ::Date.parse('1969-03-31'),
  # HST Funeral
  ::Date.parse('1972-12-28'),
  # LBJ Funeral
  ::Date.parse('1973-01-25'),
  # RMN Funeral
  ::Date.parse('1994-04-27'),
  # RWR Funeral
  ::Date.parse('2004-06-11'),
  # GTF Funeral
  ::Date.parse('2007-01-02'),
  # GHWBFuneral
  ::Date.parse('2018-12-05')
]

Constant Summary collapse

BOT =

Constant for Beginning of Time (BOT) outside the range of what we would ever want to find in commercial situations.

::Date.parse('1900-01-01')
EOT =

Constant for End of Time (EOT) outside the range of what we would ever want to find in commercial situations.

::Date.parse('3000-12-31')

Formatting collapse

Queries collapse

Relative ::Dates collapse

Federal Holidays and Workdays collapse

NYSE Holidays and Workdays collapse

Instance Method Details

#add_chunk(chunk, n = 1) ⇒ ::Date

Return the date that is n chunks later than self.



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# File 'lib/fat_core/date.rb', line 677

def add_chunk(chunk, n = 1)
  case chunk
  when :year
    next_year(n)
  when :half
    next_month(6)
  when :quarter
    next_month(3)
  when :bimonth
    next_month(2)
  when :month
    next_month(n)
  when :semimonth
    next_semimonth(n)
  when :biweek
    next_biweek(n)
  when :week
    next_week(n)
  when :day
    next_day(n)
  else
    raise ArgumentError, "add_chunk unknown chunk: '#{chunk}'"
  end
end

#add_fed_workdays(n) ⇒ ::Date

Return the date that is n federal workdays after or before (if n < 0) this date.



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# File 'lib/fat_core/date.rb', line 869

def add_fed_workdays(n)
  d = dup
  return d if n.zero?
  incr = n.negative? ? -1 : 1
  n = n.abs
  while n.positive?
    d += incr
    n -= 1 if d.fed_workday?
  end
  d
end

#add_nyse_workdays(n) ⇒ ::Date Also known as: add_trading_days

Return the date that is n NYSE trading days after or before (if n < 0) this date.



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# File 'lib/fat_core/date.rb', line 1046

def add_nyse_workdays(n)
  d = dup
  return d if n.zero?
  incr = n.negative? ? -1 : 1
  n = n.abs
  while n.positive?
    d += incr
    n -= 1 if d.nyse_workday?
  end
  d
end

#american ⇒ String

Format date in MM/DD/YYYY form, as typical for the short American form.



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# File 'lib/fat_core/date.rb', line 103

def american
  strftime '%-m/%-d/%Y'
end

#beginning_of_bimonth ⇒ ::Date

The date that is the first day of the bimonth in which self falls. A 'bimonth' is a two-month calendar period beginning on the first day of the odd-numbered months. E.g., 2014-01-01 to 2014-02-28 is the first bimonth of 2014.



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# File 'lib/fat_core/date.rb', line 394

def beginning_of_bimonth
  if month.odd?
    beginning_of_month
  else
    (self - 1.month).beginning_of_month
  end
end

#beginning_of_bimonth? ⇒ Boolean

Return whether the date falls on the first day of a calendar bi-monthly period, i.e., the beginning of an odd-numbered month.



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# File 'lib/fat_core/date.rb', line 210

def beginning_of_bimonth?
  month.odd? && beginning_of_month == self
end

#beginning_of_biweek ⇒ ::Date

Return the date that is the first day of the commercial biweek in which self falls. A biweek is a period of two commercial weeks starting with an odd-numbered week and with each week starting in Monday and ending on Sunday.



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# File 'lib/fat_core/date.rb', line 454

def beginning_of_biweek
  if cweek.odd?
    beginning_of_week(:monday)
  else
    (self - 1.week).beginning_of_week(:monday)
  end
end

#beginning_of_biweek? ⇒ Boolean

Return whether the date falls on the first day of a commercial bi-week, i.e., on /Monday/ in a commercial week that is an odd-numbered week. From ::Date: "The calendar week is a seven day period within a calendar year, starting on a Monday and identified by its ordinal number within the year; the first calendar week of the year is the one that includes the first Thursday of that year. In the Gregorian calendar, this is equivalent to the week which includes January 4."



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# File 'lib/fat_core/date.rb', line 267

def beginning_of_biweek?
  beginning_of_biweek == self
end

#beginning_of_chunk(chunk) ⇒ ::Date

Return the date that is the beginning of the +chunk+ in which this date falls.



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# File 'lib/fat_core/date.rb', line 709

def beginning_of_chunk(chunk)
  case chunk
  when :year
    beginning_of_year
  when :half
    beginning_of_half
  when :quarter
    beginning_of_quarter
  when :bimonth
    beginning_of_bimonth
  when :month
    beginning_of_month
  when :semimonth
    beginning_of_semimonth
  when :biweek
    beginning_of_biweek
  when :week
    beginning_of_week
  when :day
    self
  else
    raise ArgumentError, "unknown chunk sym: '#{chunk}'"
  end
end

#beginning_of_half ⇒ ::Date

The date that is the first day of the half-year in which self falls.



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# File 'lib/fat_core/date.rb', line 363

def beginning_of_half
  if month > 9
    (beginning_of_quarter - 15).beginning_of_quarter
  elsif month > 6
    beginning_of_quarter
  else
    beginning_of_year
  end
end

#beginning_of_half? ⇒ Boolean

Return whether the date falls on the first day of a half-year.



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# File 'lib/fat_core/date.rb', line 177

def beginning_of_half?
  beginning_of_half == self
end

#beginning_of_month? ⇒ Boolean

Return whether the date falls on the first day of a calendar month.



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# File 'lib/fat_core/date.rb', line 227

def beginning_of_month?
  beginning_of_month == self
end

#beginning_of_quarter? ⇒ Boolean

Return whether the date falls on the first day of a calendar quarter.



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# File 'lib/fat_core/date.rb', line 193

def beginning_of_quarter?
  beginning_of_quarter == self
end

#beginning_of_semimonth ⇒ ::Date

The date that is the first day of the semimonth in which self falls. A semimonth is a calendar period beginning on the 1st or 16th of each month and ending on the 15th or last day of the month respectively. So each year has exactly 24 semimonths.



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# File 'lib/fat_core/date.rb', line 424

def beginning_of_semimonth
  if day >= 16
    ::Date.new(year, month, 16)
  else
    beginning_of_month
  end
end

#beginning_of_semimonth? ⇒ Boolean

Return whether the date falls on the first day of a calendar semi-monthly period, i.e., on the 1st or 15th of a month.



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# File 'lib/fat_core/date.rb', line 244

def beginning_of_semimonth?
  beginning_of_semimonth == self
end

#beginning_of_week? ⇒ Boolean

Return whether the date falls on the first day of a commercial week, i.e., on /Monday/ in a commercial week. From ::Date: "The calendar week is a seven day period within a calendar year, starting on a Monday and identified by its ordinal number within the year; the first calendar week of the year is the one that includes the first Thursday of that year. In the Gregorian calendar, this is equivalent to the week which includes January 4."



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# File 'lib/fat_core/date.rb', line 294

def beginning_of_week?
  beginning_of_week == self
end

#beginning_of_year? ⇒ Boolean

Return whether the date falls on the first day of a year.



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# File 'lib/fat_core/date.rb', line 161

def beginning_of_year?
  beginning_of_year == self
end

#easter? ⇒ Boolean

Return whether this date is Easter Sunday for the year in which it falls according to the Western Church. A few holidays key off this date as "moveable feasts."



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# File 'lib/fat_core/date.rb', line 331

def easter?
  # Am I Easter?
  self == easter_this_year
end

#easter_this_year ⇒ ::Date

Return the date for Easter in the Western Church for the year in which this date falls.



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# File 'lib/fat_core/date.rb', line 770

def easter_this_year
  # Return the date of Easter in self's year
  ::Date.easter(year)
end

#end_of_bimonth ⇒ ::Date

The date that is the last day of the bimonth in which self falls. A 'bimonth' is a two-month calendar period beginning on the first day of the odd-numbered months. E.g., 2014-01-01 to 2014-02-28 is the first bimonth of 2014.



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# File 'lib/fat_core/date.rb', line 409

def end_of_bimonth
  if month.odd?
    (self + 1.month).end_of_month
  else
    end_of_month
  end
end

#end_of_bimonth? ⇒ Boolean

Return whether the date falls on the last day of a calendar bi-monthly period, i.e., the end of an even-numbered month.



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# File 'lib/fat_core/date.rb', line 219

def end_of_bimonth?
  month.even? && end_of_month == self
end

#end_of_biweek ⇒ ::Date

Return the date that is the last day of the commercial biweek in which self falls. A biweek is a period of two commercial weeks starting with an odd-numbered week and with each week starting in Monday and ending on Sunday. So this will always return a Sunday in an even-numbered week.



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# File 'lib/fat_core/date.rb', line 469

def end_of_biweek
  if cweek.odd?
    (self + 1.week).end_of_week(:monday)
  else
    end_of_week(:monday)
  end
end

#end_of_biweek? ⇒ Boolean

Return whether the date falls on the last day of a commercial bi-week, i.e., on /Sunday/ in a commercial week that is an even-numbered week. From ::Date: "The calendar week is a seven day period within a calendar year, starting on a Monday and identified by its ordinal number within the year; the first calendar week of the year is the one that includes the first Thursday of that year. In the Gregorian calendar, this is equivalent to the week which includes January 4."



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# File 'lib/fat_core/date.rb', line 281

def end_of_biweek?
  end_of_biweek == self
end

#end_of_chunk(chunk) ⇒ ::Date

Return the date that is the end of the +chunk+ in which this date falls.



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# File 'lib/fat_core/date.rb', line 741

def end_of_chunk(chunk)
  case chunk
  when :year
    end_of_year
  when :half
    end_of_half
  when :quarter
    end_of_quarter
  when :bimonth
    end_of_bimonth
  when :month
    end_of_month
  when :semimonth
    end_of_semimonth
  when :biweek
    end_of_biweek
  when :week
    end_of_week
  when :day
    self
  else
    raise ArgumentError, "unknown chunk: '#{chunk}'"
  end
end

#end_of_half ⇒ ::Date

The date that is the last day of the half-year in which self falls.



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# File 'lib/fat_core/date.rb', line 377

def end_of_half
  if month < 4
    (end_of_quarter + 15).end_of_quarter
  elsif month < 7
    end_of_quarter
  else
    end_of_year
  end
end

#end_of_half? ⇒ Boolean

Return whether the date falls on the last day of a half-year.



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# File 'lib/fat_core/date.rb', line 185

def end_of_half?
  end_of_half == self
end

#end_of_month? ⇒ Boolean

Return whether the date falls on the last day of a calendar month.



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# File 'lib/fat_core/date.rb', line 235

def end_of_month?
  end_of_month == self
end

#end_of_quarter? ⇒ Boolean

Return whether the date falls on the last day of a calendar quarter.



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# File 'lib/fat_core/date.rb', line 201

def end_of_quarter?
  end_of_quarter == self
end

#end_of_semimonth ⇒ ::Date

The date that is the last day of the semimonth in which self falls. A semimonth is a calendar period beginning on the 1st or 16th of each month and ending on the 15th or last day of the month respectively. So each year has exactly 24 semimonths.



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# File 'lib/fat_core/date.rb', line 439

def end_of_semimonth
  if day <= 15
    ::Date.new(year, month, 15)
  else
    end_of_month
  end
end

#end_of_semimonth? ⇒ Boolean

Return whether the date falls on the last day of a calendar semi-monthly period, i.e., on the 14th or the last day of a month.



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# File 'lib/fat_core/date.rb', line 253

def end_of_semimonth?
  end_of_semimonth == self
end

#end_of_week? ⇒ Boolean

Return whether the date falls on the first day of a commercial week, i.e., on /Sunday/ in a commercial week. From ::Date: "The calendar week is a seven day period within a calendar year, starting on a Monday and identified by its ordinal number within the year; the first calendar week of the year is the one that includes the first Thursday of that year. In the Gregorian calendar, this is equivalent to the week which includes January 4."



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# File 'lib/fat_core/date.rb', line 307

def end_of_week?
  end_of_week == self
end

#end_of_year? ⇒ Boolean

Return whether the date falls on the last day of a year.



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# File 'lib/fat_core/date.rb', line 169

def end_of_year?
  end_of_year == self
end

#eng ⇒ String

Format as an English string, like 'January 12, 2016'



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# File 'lib/fat_core/date.rb', line 94

def eng
  strftime('%B %-d, %Y')
end

#fed_holiday? ⇒ Boolean

Return whether this date is a United States federal holiday.

Calculations for Federal holidays are based on 5 USC 6103, include all weekends, Presidential funerals, and holidays decreed executive orders.



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# File 'lib/fat_core/date.rb', line 813

def fed_holiday?
  # All Saturdays and Sundays are "holidays"
  return true if weekend?

  # Some days are holidays by executive decree
  return true if FED_DECREED_HOLIDAYS.include?(self)

  # Presidential funerals
  return true if PRESIDENTIAL_FUNERALS.include?(self)

  # Is self a fixed holiday
  return true if fed_fixed_holiday? || fed_moveable_feast?

  if friday? && month == 12 && day == 26
    # If Christmas falls on a Thursday, apparently, the Friday after is
    # treated as a holiday as well.  See 2003, 2008, for example.
    true
  elsif friday?
    # A Friday is a holiday if a fixed-date holiday
    # would fall on the following Saturday
    (self + 1).fed_fixed_holiday? || (self + 1).fed_moveable_feast?
  elsif monday?
    # A Monday is a holiday if a fixed-date holiday
    # would fall on the preceding Sunday
    (self - 1).fed_fixed_holiday? || (self - 1).fed_moveable_feast?
  elsif (year % 4 == 1) && year > 1965 && mon == 1 && mday == 20
    # Inauguration Day after 1965 is a federal holiday, but if it falls on a
    # Sunday, the following Monday is observed, but if it falls on a
    # Saturday, the prior Friday is /not/ observed. So, we can't just count
    # this as a regular fixed holiday.
    true
  elsif monday? && (year % 4 == 1) && year > 1965 && mon == 1 && mday == 21
    # Inauguration Day after 1965 is a federal holiday, but if it falls on a
    # Sunday, the following Monday is observed, but if it falls on a
    # Saturday, the prior Friday is /not/ observed.
    true
  else
    false
  end
end

#fed_workday? ⇒ Boolean

Return whether this date is a date on which the US federal government is open for business. It is the opposite of #fed_holiday?



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# File 'lib/fat_core/date.rb', line 858

def fed_workday?
  !fed_holiday?
end

#half ⇒ 1, 2

Self's calendar "half" by analogy to calendar quarters: 1 or 2, depending on whether the date falls in the first or second half of the calendar year.



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# File 'lib/fat_core/date.rb', line 130

def half
  case month
  when (1..6)
    1
  when (7..12)
    2
  end
end

#iso ⇒ String

Format as an ISO string of the form YYYY-MM-DD.



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# File 'lib/fat_core/date.rb', line 61

def iso
  strftime('%Y-%m-%d')
end

#next_bimonth(n = 1) ⇒ ::Date

Return the date that is +n+ calendar bimonths after this date, where a calendar bimonth is a period of 2 months.



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# File 'lib/fat_core/date.rb', line 522

def next_bimonth(n = 1)
  n = n.floor
  return self if n.zero?
  next_month(n * 2)
end

#next_biweek(n = 1) ⇒ ::Date

Return the date that is +n+ biweeks after this date where each biweek is 14 days.



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# File 'lib/fat_core/date.rb', line 621

def next_biweek(n = 1)
  n = n.floor
  return self if n.zero?
  self + (14 * n)
end

#next_fed_workday ⇒ ::Date

Return the next federal workday after this date. The date returned is always a date at least one day after this date, never this date.



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# File 'lib/fat_core/date.rb', line 885

def next_fed_workday
  add_fed_workdays(1)
end

#next_half(n = 1) ⇒ ::Date

Return the date that is +n+ calendar halves after this date, where a calendar half is a period of 6 months.



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# File 'lib/fat_core/date.rb', line 482

def next_half(n = 1)
  n = n.floor
  return self if n.zero?
  next_month(n * 6)
end

#next_nyse_workday ⇒ ::Date Also known as: next_trading_day

Return the next NYSE trading day after this date. The date returned is always a date at least one day after this date, never this date.



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# File 'lib/fat_core/date.rb', line 1063

def next_nyse_workday
  add_nyse_workdays(1)
end

#next_quarter(n = 1) ⇒ ::Date

Return the date that is +n+ calendar quarters after this date, where a calendar quarter is a period of 3 months.



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# File 'lib/fat_core/date.rb', line 502

def next_quarter(n = 1)
  n = n.floor
  return self if n.zero?
  next_month(n * 3)
end

#next_semimonth(n = 1) ⇒ ::Date

Return the date that is +n+ semimonths after this date. Each semimonth begins on the 1st or 16th of the month, and advancing one semimonth from the first half of a month means to go as far past the 16th as the current date is past the 1st; advancing one semimonth from the second half of a month means to go as far into the next month past the 1st as the current date is past the 16th, but never past the 15th of the next month.



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# File 'lib/fat_core/date.rb', line 546

def next_semimonth(n = 1)
  n = n.floor
  return self if n.zero?
  factor = n.negative? ? -1 : 1
  n = n.abs
  if n.even?
    next_month(n / 2)
  else
    # Advance or retreat one semimonth
    next_sm =
      if day == 1
        if factor.positive?
          beginning_of_month + 16.days
        else
          prior_month.beginning_of_month + 16.days
        end
      elsif day == 16
        if factor.positive?
          next_month.beginning_of_month
        else
          beginning_of_month
        end
      elsif day < 16
        # In the first half of the month (the 2nd to the 15th), go as far past
        # the 16th as the date is past the 1st. Thus, as many as 14 days past
        # the 16th, so at most to the 30th of the month unless there are less
        # than 30 days in the month, then go to the end of the month.
        if factor.positive?
          [beginning_of_month + 16.days + (day - 1).days, end_of_month].min
        else
          [prior_month.beginning_of_month + 16.days + (day - 1).days,
           prior_month.end_of_month].min
        end
      else
        # In the second half of the month (17th to the 31st), go as many
        # days into the next month as we are past the 16th. Thus, as many as
        # 15 days.  But we don't want to go past the first half of the next
        # month, so we only go so far as the 15th of the next month.
        # ::Date.parse('2015-02-18').next_semimonth should be the 3rd of the
        # following month.
        if factor.positive?
          next_month.beginning_of_month + [(day - 16), 15].min
        else
          beginning_of_month + [(day - 16), 15].min
        end
      end
    n -= 1
    # Now that n is even, advance (or retreat) n / 2 months unless we're done.
    if n >= 2
      next_sm.next_month(factor * n / 2)
    else
      next_sm
    end
  end
end

#next_until_fed_workday ⇒ ::Date

Return this date if its a federal workday, otherwise skip forward to the first later federal workday.



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# File 'lib/fat_core/date.rb', line 901

def next_until_fed_workday
  date = dup
  date += 1 until date.fed_workday?
  date
end

#next_until_trading_day ⇒ ::Date

Return this date if its a trading day, otherwise skip forward to the first later trading day.



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# File 'lib/fat_core/date.rb', line 1081

def next_until_trading_day
  date = dup
  date += 1 until date.trading_day?
  date
end

#next_week(n = 1) ⇒ ::Date

Return the date that is +n+ weeks after this date where each week is 7 days. This is different from the #next_week method in active_support, which goes to the first day of the week in the next week and does not take an argument +n+ to go multiple weeks.



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# File 'lib/fat_core/date.rb', line 643

def next_week(n = 1)
  n = n.floor
  return self if n.zero?
  self + (7 * n)
end

#nth_wday_in_month?(n, wday, month) ⇒ Boolean

Return whether this date is the nth weekday wday of the given month in this date's year.



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# File 'lib/fat_core/date.rb', line 344

def nth_wday_in_month?(n, wday, month)
  # Is self the nth weekday in the given month of its year?
  # If n is negative, count from last day of month
  self == ::Date.nth_wday_in_year_month(n, wday, year, month)
end

#num ⇒ String

Format as an all-numeric string of the form YYYYMMDD



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# File 'lib/fat_core/date.rb', line 77

def num
  strftime('%Y%m%d')
end

#nyse_holiday? ⇒ Boolean

Returns whether this date is one on which the NYSE was or is expected to be closed for business.

Calculations for NYSE holidays are from Rule 51 and supplementary materials for the Rules of the New York Stock Exchange, Inc.

  • General Rule 1: if a regular holiday falls on Saturday, observe it on the preceding Friday.
  • General Rule 2: if a regular holiday falls on Sunday, observe it on the following Monday.

These are the regular holidays:

  • New Year's Day, January 1.
  • Birthday of Martin Luther King, Jr., the third Monday in January.
  • Washington's Birthday, the third Monday in February.
  • Good Friday Friday before Easter Sunday. NOTE: this is not a fed holiday
  • Memorial Day, the last Monday in May.
  • Independence Day, July 4.
  • Labor Day, the first Monday in September.
  • Thanksgiving Day, the fourth Thursday in November.
  • Christmas Day, December 25.

Columbus and Veterans days not observed.

In addition, there have been several days on which the exchange has been closed for special events such as Presidential funerals, the 9-11 attacks, the paper-work crisis in the 1960's, hurricanes, etc. All of these are considered holidays for purposes of this method.

In addition, every weekend is considered a holiday.



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# File 'lib/fat_core/date.rb', line 1002

def nyse_holiday?
  # All Saturdays and Sundays are "holidays"
  return true if weekend?

  # Presidential funerals, observed by NYSE as well.
  return true if PRESIDENTIAL_FUNERALS.include?(self)

  # Is self a fixed holiday
  return true if nyse_fixed_holiday? || nyse_moveable_feast?

  return true if nyse_special_holiday?

  if friday? && (self >= ::Date.parse('1959-07-03'))
    # A Friday is a holiday if a holiday would fall on the following
    # Saturday.  The rule does not apply if the Friday "ends a monthly or
    # yearly accounting period." Adopted July 3, 1959. E.g, December 31,
    # 2010, fell on a Friday, so New Years was on Saturday, but the NYSE
    # opened because it ended a yearly accounting period.  I believe 12/31
    # is the only date to which the exception can apply since only New
    # Year's can fall on the first of the month.
    !end_of_quarter? &&
      ((self + 1).nyse_fixed_holiday? || (self + 1).nyse_moveable_feast?)
  elsif monday?
    # A Monday is a holiday if a holiday would fall on the
    # preceding Sunday.  This has apparently always been the rule.
    (self - 1).nyse_fixed_holiday? || (self - 1).nyse_moveable_feast?
  else
    false
  end
end

#nyse_workday? ⇒ Boolean Also known as: trading_day?

Return whether the NYSE is open for trading on this date.



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# File 'lib/fat_core/date.rb', line 1036

def nyse_workday?
  !nyse_holiday?
end

#org ⇒ String

Format as an inactive Org date timestamp of the form [YYYY-MM-DD <dow>] (see Emacs org-mode)



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# File 'lib/fat_core/date.rb', line 86

def org
  strftime('[%Y-%m-%d %a]')
end

#pred ⇒ ::Date

Predecessor of self, opposite of #succ.



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# File 'lib/fat_core/date.rb', line 355

def pred
  self - 1.day
end

#prior_bimonth(n = 1) ⇒ ::Date

Return the date that is +n+ calendar bimonths before this date, where a calendar bimonth is a period of 2 months.



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# File 'lib/fat_core/date.rb', line 533

def prior_bimonth(n = 1)
  next_bimonth(-n)
end

#prior_biweek(n = 1) ⇒ ::Date

Return the date that is +n+ biweeks before this date where each biweek is 14 days.



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# File 'lib/fat_core/date.rb', line 632

def prior_biweek(n = 1)
  next_biweek(-n)
end

#prior_day(n) ⇒ ::Date

Return the date that is +n+ weeks before this date where each week is 7 days.



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# File 'lib/fat_core/date.rb', line 665

def prior_day(n)
  next_day(-n)
end

#prior_fed_workday ⇒ ::Date

Return the last federal workday before this date. The date returned is always a date at least one day before this date, never this date.



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# File 'lib/fat_core/date.rb', line 893

def prior_fed_workday
  add_fed_workdays(-1)
end

#prior_half(n = 1) ⇒ ::Date

Return the date that is +n+ calendar halves before this date, where a calendar half is a period of 6 months.



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# File 'lib/fat_core/date.rb', line 493

def prior_half(n = 1)
  next_half(-n)
end

#prior_nyse_workday ⇒ ::Date Also known as: prior_trading_day

Return the last NYSE trading day before this date. The date returned is always a date at least one day before this date, never this date.



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# File 'lib/fat_core/date.rb', line 1072

def prior_nyse_workday
  add_nyse_workdays(-1)
end

#prior_quarter(n = 1) ⇒ ::Date

Return the date that is +n+ calendar quarters before this date, where a calendar quarter is a period of 3 months.



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# File 'lib/fat_core/date.rb', line 513

def prior_quarter(n = 1)
  next_quarter(-n)
end

#prior_semimonth(n = 1) ⇒ ::Date

Return the date that is +n+ semimonths before this date. Each semimonth begins on the 1st or 15th of the month, and retreating one semimonth from the first half of a month means to go as far past the 15th of the prior month as the current date is past the 1st; retreating one semimonth from the second half of a month means to go as far past the 1st of the current month as the current date is past the 15th, but never past the 14th of the the current month.



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# File 'lib/fat_core/date.rb', line 612

def prior_semimonth(n = 1)
  next_semimonth(-n)
end

#prior_until_fed_workday ⇒ Object

Return this if its a federal workday, otherwise skip back to the first prior federal workday.



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# File 'lib/fat_core/date.rb', line 909

def prior_until_fed_workday
  date = dup
  date -= 1 until date.fed_workday?
  date
end

#prior_until_trading_day ⇒ ::Date

Return this date if its a trading day, otherwise skip back to the first prior trading day.



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# File 'lib/fat_core/date.rb', line 1091

def prior_until_trading_day
  date = dup
  date -= 1 until date.trading_day?
  date
end

#prior_week(n) ⇒ ::Date

Return the date that is +n+ weeks before this date where each week is 7 days.



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# File 'lib/fat_core/date.rb', line 654

def prior_week(n)
  next_week(-n)
end

#quarter ⇒ 1, ...

Self's calendar quarter: 1, 2, 3, or 4, depending on which calendar quarter the date falls in.



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# File 'lib/fat_core/date.rb', line 144

def quarter
  case month
  when (1..3)
    1
  when (4..6)
    2
  when (7..9)
    3
  when (10..12)
    4
  end
end

#tex_quote ⇒ String

Format date to TeX documents as ISO strings



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# File 'lib/fat_core/date.rb', line 69

def tex_quote
  iso
end

#weekday? ⇒ Boolean

Does self fall on a weekday?



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# File 'lib/fat_core/date.rb', line 120

def weekday?
  !weekend?
end

#weekend? ⇒ Boolean

Does self fall on a weekend?



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# File 'lib/fat_core/date.rb', line 112

def weekend?
  saturday? || sunday?
end

#within_6mos_of?(d) ⇒ Boolean

Return whether this date falls within a period of less than six months from the date d using the Stella v. Graham Page Motors convention that "less" than six months is true only if this date falls within the range of dates 2 days after date six months before and 2 days before the date six months after the date d.



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# File 'lib/fat_core/date.rb', line 319

def within_6mos_of?(d)
  # ::Date 6 calendar months before self
  start_date = self - 6.months + 2.days
  end_date = self + 6.months - 2.days
  (start_date..end_date).cover?(d)
end