diff options
author | tadf <tadf@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2008-01-06 00:39:44 +0000 |
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committer | tadf <tadf@b2dd03c8-39d4-4d8f-98ff-823fe69b080e> | 2008-01-06 00:39:44 +0000 |
commit | 5781f2b44c1b967903016b08c865f066736672c6 (patch) | |
tree | 76ff79ab4116ca57f936423dd39cceadfd1a4cef /lib/date.rb | |
parent | 636089ddbebe54616d010f2296ae1182b195593d (diff) |
* lib/date.rb, lib/date/format.rb: introduced some constants
(for internal use) and aliases (minute and second).
* sample/cal.rb: trivial adjustments.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@14904 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
Diffstat (limited to 'lib/date.rb')
-rw-r--r-- | lib/date.rb | 85 |
1 files changed, 56 insertions, 29 deletions
diff --git a/lib/date.rb b/lib/date.rb index ce24802371..bc75b198af 100644 --- a/lib/date.rb +++ b/lib/date.rb @@ -1,12 +1,12 @@ # # date.rb - date and time library # -# Author: Tadayoshi Funaba 1998-2007 +# Author: Tadayoshi Funaba 1998-2008 # # Documentation: William Webber <william@williamwebber.com> # #-- -# $Id: date.rb,v 2.34 2007-12-30 21:45:27+09 tadf Exp $ +# $Id: date.rb,v 2.35 2008-01-06 08:42:17+09 tadf Exp $ #++ # # == Overview @@ -313,7 +313,20 @@ class Date # Gregorian calendar. GREGORIAN = -Infinity.new - UNIXEPOCH = 2440588 # 1970-01-01 :nodoc: + HALF_DAYS_IN_DAY = Rational(1, 2) # :nodoc: + HOURS_IN_DAY = Rational(1, 24) # :nodoc: + MINUTES_IN_DAY = Rational(1, 1440) # :nodoc: + SECONDS_IN_DAY = Rational(1, 86400) # :nodoc: + MILLISECONDS_IN_DAY = Rational(1, 86400*10**3) # :nodoc: + NANOSECONDS_IN_DAY = Rational(1, 86400*10**9) # :nodoc: + MILLISECONDS_IN_SECOND = Rational(1, 10**3) # :nodoc: + NANOSECONDS_IN_SECOND = Rational(1, 10**9) # :nodoc: + + MJD_EPOCH_IN_AJD = Rational(4800001, 2) # 1858-11-17 # :nodoc: + UNIX_EPOCH_IN_AJD = Rational(4881175, 2) # 1970-01-01 # :nodoc: + MJD_EPOCH_IN_CJD = 2400001 # :nodoc: + UNIX_EPOCH_IN_CJD = 2440588 # :nodoc: + LD_EPOCH_IN_CJD = 2299160 # :nodoc: # Does a given Julian Day Number fall inside the old-style (Julian) # calendar? @@ -476,7 +489,7 @@ class Date # # Returns the (civil) Julian Day Number as [day_number, # fraction] where +fraction+ is always 1/2. - def self.ajd_to_jd(ajd, of=0) (ajd + of + 1.to_r/2).divmod(1) end + def self.ajd_to_jd(ajd, of=0) (ajd + of + HALF_DAYS_IN_DAY).divmod(1) end # Convert a (civil) Julian Day Number to an Astronomical Julian # Day Number. @@ -487,46 +500,54 @@ class Date # # Returns the Astronomical Julian Day Number as a single # numeric value. - def self.jd_to_ajd(jd, fr, of=0) jd + fr - of - 1.to_r/2 end + def self.jd_to_ajd(jd, fr, of=0) jd + fr - of - HALF_DAYS_IN_DAY end # Convert a fractional day +fr+ to [hours, minutes, seconds, # fraction_of_a_second] def self.day_fraction_to_time(fr) - h, fr = fr.divmod(1.to_r/24) - min, fr = fr.divmod(1.to_r/1440) - s, fr = fr.divmod(1.to_r/86400) + h, fr = fr.divmod(HOURS_IN_DAY) + min, fr = fr.divmod(MINUTES_IN_DAY) + s, fr = fr.divmod(SECONDS_IN_DAY) return h, min, s, fr end # Convert an +h+ hour, +min+ minutes, +s+ seconds period # to a fractional day. - def self.time_to_day_fraction(h, min, s) - h.to_r/24 + min.to_r/1440 + s.to_r/86400 + begin + Rational(Rational(1, 2), 2) # a challenge + + def self.time_to_day_fraction(h, min, s) + Rational(h, 24) + Rational(min, 1440) + Rational(s, 86400) + end + rescue + def self.time_to_day_fraction(h, min, s) + h.to_r/24 + min.to_r/1440 + s.to_r/86400 + end end # Convert an Astronomical Modified Julian Day Number to an # Astronomical Julian Day Number. - def self.amjd_to_ajd(amjd) amjd + 4800001.to_r/2 end + def self.amjd_to_ajd(amjd) amjd + MJD_EPOCH_IN_AJD end # Convert an Astronomical Julian Day Number to an # Astronomical Modified Julian Day Number. - def self.ajd_to_amjd(ajd) ajd - 4800001.to_r/2 end + def self.ajd_to_amjd(ajd) ajd - MJD_EPOCH_IN_AJD end # Convert a Modified Julian Day Number to a Julian # Day Number. - def self.mjd_to_jd(mjd) mjd + 2400001 end + def self.mjd_to_jd(mjd) mjd + MJD_EPOCH_IN_CJD end # Convert a Julian Day Number to a Modified Julian Day # Number. - def self.jd_to_mjd(jd) jd - 2400001 end + def self.jd_to_mjd(jd) jd - MJD_EPOCH_IN_CJD end # Convert a count of the number of days since the adoption # of the Gregorian Calendar (in Italy) to a Julian Day Number. - def self.ld_to_jd(ld) ld + 2299160 end + def self.ld_to_jd(ld) ld + LD_EPOCH_IN_CJD end # Convert a Julian Day Number to the number of days since # the adoption of the Gregorian Calendar (in Italy). - def self.jd_to_ld(jd) jd - 2299160 end + def self.jd_to_ld(jd) jd - LD_EPOCH_IN_CJD end # Convert a Julian Day Number to the day of the week. # @@ -768,7 +789,7 @@ class Date h, fr = fr.divmod(3600) min, fr = fr.divmod(60) s, fr = fr.divmod(1) - elem[:jd] = UNIXEPOCH + d + elem[:jd] = UNIX_EPOCH_IN_CJD + d elem[:hour] = h elem[:min] = min elem[:sec] = s @@ -1096,7 +1117,14 @@ class Date # I do NOT recommend you to use this method. def sec_fraction() time[3] end +=begin + alias_method :minute, :min + alias_method :second, :sec + alias_method :second_fraction, :sec_fraction +=end + private :hour, :min, :sec, :sec_fraction +# :minute, :second, :second_fraction def zone() strftime('%:z') end @@ -1181,7 +1209,7 @@ class Date def new_offset(of=0) if String === of - of = (self.class.zone_to_diff(of) || 0).to_r/86400 + of = Rational(zone_to_diff(of) || 0, 86400) end self.class.new!(@ajd, of, @sg) end @@ -1437,7 +1465,7 @@ class DateTime < Date raise ArgumentError, 'invalid date' end if String === of - of = (zone_to_diff(of) || 0).to_r/86400 + of = Rational(zone_to_diff(of) || 0, 86400) end new!(jd_to_ajd(jd, fr, of), of, sg) end @@ -1462,7 +1490,7 @@ class DateTime < Date raise ArgumentError, 'invalid date' end if String === of - of = (zone_to_diff(of) || 0).to_r/86400 + of = Rational(zone_to_diff(of) || 0, 86400) end new!(jd_to_ajd(jd, fr, of), of, sg) end @@ -1487,7 +1515,7 @@ class DateTime < Date raise ArgumentError, 'invalid date' end if String === of - of = (zone_to_diff(of) || 0).to_r/86400 + of = Rational(zone_to_diff(of) || 0, 86400) end new!(jd_to_ajd(jd, fr, of), of, sg) end @@ -1515,7 +1543,7 @@ class DateTime < Date raise ArgumentError, 'invalid date' end if String === of - of = (zone_to_diff(of) || 0).to_r/86400 + of = Rational(zone_to_diff(of) || 0, 86400) end new!(jd_to_ajd(jd, fr, of), of, sg) end @@ -1526,7 +1554,7 @@ class DateTime < Date raise ArgumentError, 'invalid date' end if String === of - of = (zone_to_diff(of) || 0).to_r/86400 + of = Rational(zone_to_diff(of) || 0, 86400) end new!(jd_to_ajd(jd, fr, of), of, sg) end @@ -1540,10 +1568,8 @@ class DateTime < Date (fr = valid_time_frags?(elem)) raise ArgumentError, 'invalid date' end - sf = (elem[:sec_fraction] || 0) - fr += sf/86400 - of = (elem[:offset] || 0) - of = of.to_r/86400 + fr += (elem[:sec_fraction] || 0) / 86400 + of = Rational(elem[:offset] || 0, 86400) new!(jd_to_ajd(jd, fr, of), of, sg) end @@ -1589,6 +1615,7 @@ class DateTime < Date end public :hour, :min, :sec, :sec_fraction, :zone, :offset, :new_offset +# :minute, :second, :second_fraction end @@ -1604,8 +1631,8 @@ class Time def to_datetime jd = DateTime.civil_to_jd(year, mon, mday, DateTime::ITALY) fr = DateTime.time_to_day_fraction(hour, min, [sec, 59].min) + - usec.to_r/86400000000 - of = utc_offset.to_r/86400 + Rational(usec, 86400_000_000) + of = Rational(utc_offset, 86400) DateTime.new!(DateTime.jd_to_ajd(jd, fr, of), of, DateTime::ITALY) end |