# # Gramps - a GTK+/GNOME based genealogy program # # Copyright (C) 2001 Donald N. Allingham # # This program is free software; you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation; either version 2 of the License, or # (at your option) any later version. # # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # """ Calendar conversion routines for GRAMPS. The original algorithms for this module came from Scott E. Lee's C implementation. The original C source can be found at Scott's web site at http://www.scottlee.com """ __author__ = "Donald N. Allingham" __version__ = "$Revision$" _FR_SDN_OFFSET = 2375474 _FR_DAYS_PER_4_YEARS = 1461 _FR_DAYS_PER_MONTH = 30 _FR_FIRST_VALID = 2375840 _FR_LAST_VALID = 2380952 _GR_SDN_OFFSET = 32045 _GR_DAYS_PER_5_MONTHS = 153 _GR_DAYS_PER_4_YEARS = 1461 _GR_DAYS_PER_400_YEARS = 146097 _J_SDN_OFFSET = 32083 _J_DAYS_PER_5_MONTHS = 153 _J_DAYS_PER_4_YEARS = 1461 _HALAKIM_PER_HOUR = 1080 _HALAKIM_PER_DAY = 25920 _HALAKIM_PER_LUNAR_CYCLE = ((29 * _HALAKIM_PER_DAY) + 13753) _HALAKIM_PER_METONIC_CYCLE = (_HALAKIM_PER_LUNAR_CYCLE * (12 * 19 + 7)) _H_SDN_OFFSET = 347997 _NEW_MOON_OF_CREATION = 31524 _SUNDAY = 0 _MONDAY = 1 _TUESDAY = 2 _WEDNESDAY= 3 #_THURSDAY = 4 _FRIDAY = 5 #_SATURDAY = 6 _NOON = (18 * _HALAKIM_PER_HOUR) _AM3_11_20 = ((9 * _HALAKIM_PER_HOUR) + 204) _AM9_32_43 = ((15 * _HALAKIM_PER_HOUR) + 589) #------------------------------------------------------------------------- # # Conversion tables # #------------------------------------------------------------------------- monthsPerYear = [ 12, 12, 13, 12, 12, 13, 12, 13, 12, 12, 13, 12, 12, 13, 12, 12, 13, 12, 13 ] yearOffset = [ 0, 12, 24, 37, 49, 61, 74, 86, 99, 111, 123, 136, 148, 160, 173, 185, 197, 210, 222 ] #------------------------------------------------------------------------- # # Tasks # #------------------------------------------------------------------------- def french_to_sdn(y,m,d): """Converts a French Republican Calendar date to an SDN number""" if (y < 1 or y > 14 or m < 1 or m > 13 or d < 1 or d > 30): return 0 return (y*_FR_DAYS_PER_4_YEARS)/4+(m-1)*_FR_DAYS_PER_MONTH+d+_FR_SDN_OFFSET def sdn_to_french(sdn): """Converts an SDN number to a French Republican Calendar date""" if (sdn < _FR_FIRST_VALID or sdn > _FR_LAST_VALID) : return (0,0,0) temp = (sdn-_FR_SDN_OFFSET)*4 - 1 year = temp/_FR_DAYS_PER_4_YEARS dayOfYear = (temp%_FR_DAYS_PER_4_YEARS)/4 month = (dayOfYear/_FR_DAYS_PER_MONTH)+1 day = (dayOfYear%_FR_DAYS_PER_MONTH)+1 return (year,month,day) def sdn_to_gregorian(sdn): """Converts an SDN number to a gregorial date""" if sdn <= 0: return (0,0,0) temp = (sdn + _GR_SDN_OFFSET) * 4 - 1 # Calculate the century (year/100) century = temp / _GR_DAYS_PER_400_YEARS # Calculate the year and day of year (1 <= dayOfYear <= 366) temp = ((temp % _GR_DAYS_PER_400_YEARS) / 4) * 4 + 3 year = (century * 100) + (temp / _GR_DAYS_PER_4_YEARS) dayOfYear = (temp % _GR_DAYS_PER_4_YEARS) / 4 + 1 # Calculate the month and day of month temp = dayOfYear * 5 - 3 month = temp / _GR_DAYS_PER_5_MONTHS day = (temp % _GR_DAYS_PER_5_MONTHS) / 5 + 1 # Convert to the normal beginning of the year if month < 10 : month = month + 3 else: year = year + 1 month = month + 9 # Adjust to the B.C./A.D. type numbering year = year - 4800 if year <= 0: year = year - 1 return (year,month,day) def gregorian_to_sdn(iyear,imonth,iday): """Converts a gregorian date to an SDN number""" # check for invalid dates if iyear==0 or iyear<-4714 or imonth<=0 or imonth>12 or iday<=0 or iday>31: return 0 # check for dates before SDN 1 (Nov 25, 4714 B.C.) if iyear == -4714: if imonth < 11 or imonth == 11 and iday < 25: return 0 if iyear < 0: year = iyear + 4801 else: year = iyear + 4800 # Adjust the start of the year if imonth > 2: month = imonth - 3 else: month = imonth + 9 year = year - 1 return( ((year / 100) * _GR_DAYS_PER_400_YEARS) / 4 + ((year % 100) * _GR_DAYS_PER_4_YEARS) / 4 + (month * _GR_DAYS_PER_5_MONTHS + 2) / 5 + iday - _GR_SDN_OFFSET ); def sdn_to_julian(sdn): """Converts an SDN number to a Julian date""" if sdn <= 0 : return (0,0,0) temp = (sdn + _J_SDN_OFFSET) * 4 - 1 # Calculate the year and day of year (1 <= dayOfYear <= 366) year = temp / _J_DAYS_PER_4_YEARS dayOfYear = (temp % _J_DAYS_PER_4_YEARS) / 4 + 1 # Calculate the month and day of month temp = dayOfYear * 5 - 3; month = temp / _J_DAYS_PER_5_MONTHS; day = (temp % _J_DAYS_PER_5_MONTHS) / 5 + 1; # Convert to the normal beginning of the year if month < 10: month = month + 3 else: year = year + 1 month = month - 9 # Adjust to the B.C./A.D. type numbering year = year - 4800 if year <= 0: year = year - 1 return (year,month,day) def julian_to_sdn(iyear,imonth,iday): """Converts a Julian calendar date to an SDN number""" # check for invalid dates if iyear==0 or iyear<-4713 or imonth<=0 or imonth>12 or iday<=0 or iday>31: return 0 # check for dates before SDN 1 (Jan 2, 4713 B.C.) if iyear == -4713: if imonth == 1 and iday == 1: return 0 # Make year always a positive number if iyear < 0: year = iyear + 4801 else: year = iyear + 4800 # Adjust the start of the year if imonth > 2: month = imonth - 3 else: month = imonth + 9 year = year - 1 return (year*_J_DAYS_PER_4_YEARS)/4 + (month*_J_DAYS_PER_5_MONTHS+2)/5 + iday - _J_SDN_OFFSET def Tishri1(metonicYear, moladDay, moladHalakim): tishri1 = moladDay dow = tishri1 % 7 leapYear = metonicYear == 2 or metonicYear == 5 or metonicYear == 7 or \ metonicYear == 10 or metonicYear == 13 or metonicYear == 16 or \ metonicYear == 18 lastWasLeapYear = metonicYear == 3 or metonicYear == 6 or metonicYear == 8 or \ metonicYear == 11 or metonicYear == 14 or metonicYear == 17 or \ metonicYear == 0 # Apply rules 2, 3 and 4. if ((moladHalakim >= _NOON) or ((not leapYear) and dow == _TUESDAY and moladHalakim >= _AM3_11_20) or (lastWasLeapYear and dow == _MONDAY and moladHalakim >= _AM9_32_43)) : tishri1 = tishri1 + 1 dow = dow + 1 if dow == 7: dow = 0 # Apply rule 1 after the others because it can cause an additional # delay of one day if dow == _WEDNESDAY or dow == _FRIDAY or dow == _SUNDAY: tishri1 = tishri1 + 1 return tishri1 def MoladOfMetonicCycle(metonicCycle): # Start with the time of the first molad after creation. r1 = _NEW_MOON_OF_CREATION; # Calculate metonicCycle * HALAKIM_PER_METONIC_CYCLE. The upper 32 # bits of the result will be in r2 and the lower 16 bits will be # in r1. r1 = r1 + (metonicCycle * (_HALAKIM_PER_METONIC_CYCLE & 0xFFFF)) r2 = r1 >> 16 r2 = r2 + (metonicCycle * ((_HALAKIM_PER_METONIC_CYCLE >> 16) & 0xFFFF)) # Calculate r2r1 / HALAKIM_PER_DAY. The remainder will be in r1, the # upper 16 bits of the quotient will be in d2 and the lower 16 bits # will be in d1. d2 = r2 / _HALAKIM_PER_DAY r2 = r2 - (d2 * _HALAKIM_PER_DAY) r1 = (r2 << 16) | (r1 & 0xFFFF) d1 = r1 / _HALAKIM_PER_DAY r1 = r1 - ( d1 * _HALAKIM_PER_DAY) MoladDay = (d2 << 16) | d1 MoladHalakim = r1 return (MoladDay,MoladHalakim) def FindTishriMolad(inputDay): # Estimate the metonic cycle number. Note that this may be an under # estimate because there are 6939.6896 days in a metonic cycle not # 6940, but it will never be an over estimate. The loop below will # correct for any error in this estimate. */ metonicCycle = (inputDay + 310) / 6940 # Calculate the time of the starting molad for this metonic cycle. */ (moladDay, moladHalakim) = MoladOfMetonicCycle(metonicCycle) # If the above was an under estimate, increment the cycle number until # the correct one is found. For modern dates this loop is about 98.6% # likely to not execute, even once, because the above estimate is # really quite close. while moladDay < (inputDay - 6940 + 310): metonicCycle = metonicCycle + 1 moladHalakim = moladHalakim + _HALAKIM_PER_METONIC_CYCLE moladDay = moladDay + ( moladHalakim / _HALAKIM_PER_DAY) moladHalakim = moladHalakim % _HALAKIM_PER_DAY # Find the molad of Tishri closest to this date. for metonicYear in range(0,18): if moladDay > inputDay - 74: break moladHalakim = moladHalakim + \ (_HALAKIM_PER_LUNAR_CYCLE * monthsPerYear[metonicYear]) moladDay = moladDay + (moladHalakim / _HALAKIM_PER_DAY) moladHalakim = moladHalakim % _HALAKIM_PER_DAY else: metonicYear = metonicYear + 1 return (metonicCycle, metonicYear, moladDay, moladHalakim) def FindStartOfYear(year): pMetonicCycle = (year - 1) / 19; pMetonicYear = (year - 1) % 19; (pMoladDay, pMoladHalakim) = MoladOfMetonicCycle(pMetonicCycle) pMoladHalakim = pMoladHalakim + (_HALAKIM_PER_LUNAR_CYCLE * yearOffset[pMetonicYear]) pMoladDay = pMoladDay + (pMoladHalakim / _HALAKIM_PER_DAY) pMoladHalakim = pMoladHalakim % _HALAKIM_PER_DAY pTishri1 = Tishri1(pMetonicYear, pMoladDay, pMoladHalakim); return (pMetonicCycle, pMetonicYear, pMoladDay, pMoladHalakim, pTishri1) def sdn_to_jewish(sdn): """Converts an SDN number to a Julian calendar date""" if sdn <= _H_SDN_OFFSET : return (0,0,0) inputDay = sdn - _H_SDN_OFFSET (metonicCycle, metonicYear, day, halakim) = FindTishriMolad(inputDay) tishri1 = Tishri1(metonicYear, day, halakim); if inputDay >= tishri1: # It found Tishri 1 at the start of the year pYear = (metonicCycle * 19) + metonicYear + 1 if inputDay < tishri1 + 59: if inputDay < tishri1 + 30: pMonth = 1 pDay = inputDay - tishri1 + 1 else: pMonth = 2 pDay = inputDay - tishri1 - 29 return (pYear, pMonth, pDay) # We need the length of the year to figure this out, so find # Tishri 1 of the next year. */ halakim = halakim + (_HALAKIM_PER_LUNAR_CYCLE * monthsPerYear[metonicYear]) day = day + (halakim / _HALAKIM_PER_DAY) halakim = halakim % _HALAKIM_PER_DAY; tishri1After = Tishri1((metonicYear + 1) % 19, day, halakim); else: # It found Tishri 1 at the end of the year. pYear = metonicCycle * 19 + metonicYear if inputDay >= tishri1 - 177: # It is one of the last 6 months of the year. if inputDay > tishri1 - 30: pMonth = 13 pDay = inputDay - tishri1 + 30 elif inputDay > tishri1 - 60: pMonth = 12 pDay = inputDay - tishri1 + 60 elif inputDay > tishri1 - 89: pMonth = 11 pDay = inputDay - tishri1 + 89 elif inputDay > tishri1 - 119: pMonth = 10 pDay = inputDay - tishri1 + 119 elif inputDay > tishri1 - 148: pMonth = 9 pDay = inputDay - tishri1 + 148 else: pMonth = 8 pDay = inputDay - tishri1 + 178 return (pYear,pMonth,pDay) else: if monthsPerYear[(pYear - 1) % 19] == 13: pMonth = 7 pDay = inputDay - tishri1 + 207 if pDay > 0: return (pYear,pMonth,pDay) pMonth = pMonth - 1 pDay = pDay + 30 if pDay > 0: return (pYear,pMonth,pDay) pMonth = pMonth - 1 pDay = pDay + 30 else: pMonth = 6 pDay = inputDay - tishri1 + 207 if pDay > 0: return (pYear,pMonth,pDay) pMonth = pMonth - 1 pDay = pDay + 30 if pDay > 0: return (pYear,pMonth,pDay) pMonth = pMonth - 1 pDay = pDay + 29 if pDay > 0: return (pYear,pMonth,pDay) # We need the length of the year to figure this out, so find # Tishri 1 of this year. */ tishri1After = tishri1; (metonicCycle,metonicYear,day,halakim) = FindTishriMolad(day-365) tishri1 = Tishri1(metonicYear, day, halakim) yearLength = tishri1After - tishri1; day = inputDay - tishri1 - 29; if yearLength == 355 or yearLength == 385 : # Heshvan has 30 days if day <= 30: pMonth = 2 pDay = day return (pYear,pMonth,pDay) day = day - 30 else: # Heshvan has 29 days if day <= 29: pMonth = 2 pDay = day return (pYear,pMonth,pDay) day = day - 29 # It has to be Kislev return (pYear,3,day) def jewish_to_sdn(year, month, day): """Converts a Jewish calendar date to an SDN number""" if year <= 0 or day <= 0 or day > 30 : return 0 if month == 1 or month == 2: # It is Tishri or Heshvan - don't need the year length. (metonicCycle,metonicYear,moladDay,moladHalakim,tishri1) = FindStartOfYear(year) if month == 1: sdn = tishri1 + day - 1 else: sdn = tishri1 + day + 29 elif month == 3: # It is Kislev - must find the year length. # Find the start of the year. (metonicCycle,metonicYear,moladDay,moladHalakim,tishri1) = FindStartOfYear(year) # Find the end of the year. moladHalakim = moladHalakim + (_HALAKIM_PER_LUNAR_CYCLE*monthsPerYear[metonicYear]) moladDay = moladDay + (moladHalakim / _HALAKIM_PER_DAY) moladHalakim = moladHalakim % _HALAKIM_PER_DAY tishri1After = Tishri1((metonicYear + 1) % 19, moladDay, moladHalakim) yearLength = tishri1After - tishri1 if yearLength == 355 or yearLength == 385: sdn = tishri1 + day + 59 else: sdn = tishri1 + day + 58 elif month == 4 or month == 5 or month == 6: # It is Tevet, Shevat or Adar I - don't need the year length (metonicCycle,metonicYear,moladDay,moladHalakim,tishri1After) = FindStartOfYear(year+1) if monthsPerYear[(year - 1) % 19] == 12: lengthOfAdarIAndII = 29 else: lengthOfAdarIAndII = 59 if month == 4: sdn = tishri1After + day - lengthOfAdarIAndII - 237 elif month == 5: sdn = tishri1After + day - lengthOfAdarIAndII - 208 else: sdn = tishri1After + day - lengthOfAdarIAndII - 178 else: # It is Adar II or later - don't need the year length. (metonicCycle,metonicYear,moladDay,moladHalakim,tishri1After) = FindStartOfYear(year+1) if month == 7: sdn = tishri1After + day - 207 elif month == 8: sdn = tishri1After + day - 178 elif month == 9: sdn = tishri1After + day - 148 elif month == 10: sdn = tishri1After + day - 119 elif month == 11: sdn = tishri1After + day - 89 elif month == 12: sdn = tishri1After + day - 60 elif month == 13: sdn = tishri1After + day - 30 else: return 0 return sdn + _H_SDN_OFFSET