""" Python part of the low-level DateTime[Delta] type implementation.
Copyright (c) 1998-2001, Marc-Andre Lemburg; mailto:mal@lemburg.com
Copyright (c) 2000-2007, eGenix.com Software GmbH; mailto:info@egenix.com
See the documentation for further information on copyrights,
or contact the author. All Rights Reserved.
"""
# Import the python implementation module
from mxDateTime_python import *
from mxDateTime_python import __version__
# Singletons
oneSecond = DateTimeDelta(0,0,0,1)
oneMinute = DateTimeDelta(0,0,1)
oneHour = DateTimeDelta(0,1)
oneDay = DateTimeDelta(1)
oneWeek = DateTimeDelta(7)
Epoch = DateTimeFromAbsDateTime(1,0)
# Shortcuts for pickle; for backward compatibility only (they are now
# defined in __init__.py to further reduce the pickles length)
def _DT(absdate,abstime):
return DateTimeFromAbsDateTime(absdate,abstime)
def _DTD(seconds):
return DateTimeDeltaFromSeconds(seconds)
# Module init
class modinit:
global _time,_string,_math,_types
import time,string,math,types
_time = time
_string = string
_math = math
_types = types
del modinit
### Helpers
def _isstring(arg,
isinstance=isinstance, types=_types):
if isinstance(arg, types.StringType):
return 1
try:
if isinstance(arg, types.UnicodeType):
return 1
except AttributeError:
pass
return 0
### Compatibility APIs
# Aliases and functions to make 'from mx.DateTime import *' work much
# like 'from time import *'
def localtime(ticks=None,
# Locals:
time=_time.time,float=float,localtime=_time.localtime,
round=round,int=int,DateTime=DateTime,floor=_math.floor):
"""localtime(ticks=None)
Construct a DateTime instance using local time from ticks. If
ticks are not given, it defaults to the current time. The
result is similar to time.localtime(). Fractions of a second
are rounded to the nearest micro-second.
"""
if ticks is None:
ticks = time()
else:
ticks = float(ticks)
ticks = round(ticks, 6)
fticks = floor(ticks)
Y,M,D,h,m,s = localtime(fticks)[:6]
s = s + (ticks - fticks)
return DateTime(Y,M,D,h,m,s)
def gmtime(ticks=None,
# Locals:
time=_time.time,float=float,gmtime=_time.gmtime,
round=round,int=int,DateTime=DateTime,floor=_math.floor):
"""gmtime(ticks=None)
Construct a DateTime instance using UTC time from ticks. If
ticks are not given, it defaults to the current time. The
result is similar to time.gmtime(). Fractions of a second are
rounded to the nearest micro-second.
"""
if ticks is None:
ticks = time()
else:
ticks = float(ticks)
ticks = round(ticks, 6)
fticks = floor(ticks)
Y,M,D,h,m,s = gmtime(ticks)[:6]
s = s + (ticks - fticks)
return DateTime(Y,M,D,h,m,s)
def mktime((year,month,day,hour,minute,second,dow,doy,dst),
# Locals:
DateTime=DateTime):
"""mktime((year,month,day,hour,minute,second,dow,doy,dst))
Same as the DateTime() constructor accept that the interface
used is compatible to the similar time.mktime() API.
Note that the tuple elements dow, doy and dst are not used in
any way.
"""
return DateTime(year,month,day,hour,minute,second)
def ctime(datetime):
"""ctime(datetime)
Returns a string representation of the given DateTime instance
using the current locale's default settings.
"""
return datetime.strftime('%c')
def today(hour=0,minute=0,second=0.0,
# Locals:
localtime=_time.localtime,time=_time.time,DateTime=DateTime):
"""today(hour=0,minute=0,second=0.0)
Returns a DateTime instance for today (in local time) at the
given time (defaults to midnight).
"""
Y,M,D = localtime(time())[:3]
return DateTime(Y,M,D,hour,minute,second)
def TimeDelta(hours=0.0,minutes=0.0,seconds=0.0,
# Locals:
DateTimeDelta=DateTimeDelta):
"""TimeDelta(hours=0.0,minutes=0.0,seconds=0.0)
Returns a DateTimeDelta-object reflecting the given time
delta. Seconds can be given as float to indicate fractions.
"""
return DateTimeDelta(0,hours,minutes,seconds)
def gm2local(datetime):
""" gm2local(datetime)
Convert a DateTime instance holding UTC time to a DateTime
instance using local time.
"""
return localtime(datetime.gmticks())
def local2gm(datetime):
""" local2gm(datetime)
Convert a DateTime instance holding local time to a DateTime
instance using UTC time.
"""
return gmtime(datetime.ticks())
# Alias
gmt = utc
# Default value for DateTimeFromTJD's tjd_myriad parameter
current_myriad = localtime().tjd_myriad
def DateTimeFromTJD(tjd,tjd_myriad=current_myriad):
""" DateTimeFromTJD(tjd[,myriad])
Return a DateTime instance for the given Truncated Julian Day.
myriad defaults to the TJD myriad current at package import
time.
Note that this version of Truncated Julian Day number does
real truncation of important information. It's use is
discouraged and unsupported.
"""
return DateTimeFromAbsDays(tjd + tjd_myriad * 10000.0 - 1721425.0)
def DateTimeFromJDN(jdn):
""" DateTimeFromJDN(jdn)
Return a DateTime instance for the given Julian Day Number.
References:
-----------
Gregorian 2000-01-01 12:00:00 corresponds to JDN 2451545.0.
Gregorian 1858-11-17 00:00:00.00 corresponds to JDN 2400000.5; MJD 0.0.
Julian -4712-01-01 12:00:00.00 corresponds to JDN 0.0.
Gregorian -4713-11-24 12:00:00.00 corresponds to JDN 0.0.
"""
return DateTimeFromAbsDays(jdn - 1721425.5)
def DateTimeFromMJD(mjd):
""" DateTimeFromMJD(mjd)
Return a DateTime instance for the given Modified Julian Day
(MJD). The MJD is calculated the same way as the JDN except
that 1858-11-17 00:00:00.00 is taken as origin of the scale.
"""
return DateTimeFromAbsDays(mjd + 678575.0)
def DateTimeFrom(*args, **kws):
""" DateTimeFrom(*args, **kws)
Generic DateTime instance constructor. Can handle parsing
strings, numbers and keywords.
XXX Add support for Unicode.
"""
if len(args) == 1:
# Single argument
arg = args[0]
argtype = type(arg)
if _isstring(arg):
import Parser
return apply(Parser.DateTimeFromString, args, kws)
elif argtype is DateTimeType:
return arg
elif argtype is DateTimeDeltaType:
raise TypeError,'cannot convert DateTimeDelta to DateTime'
else:
try:
value = float(arg)
except (TypeError, ValueError):
value = int(arg)
assert not kws
return DateTimeFromTicks(value)
elif len(args) > 1:
# More than one argument
if len(args) == 2 and _isstring(args[0]) and _isstring(args[1]):
# interpret as date and time string
import Parser
return apply(Parser.DateTimeFromString,
(args[0] + ' ' + args[1],),
kws)
# Assume the arguments are the same as for DateTime()
return apply(DateTime, args, kws)
elif len(kws) > 0:
# Keyword arguments; add defaults... today at 0:00:00
hour = kws.get('hour',0)
minute = kws.get('minute',0)
second = kws.get('second',0)
today = now()
day = kws.get('day',today.day)
month = kws.get('month',today.month)
year = kws.get('year',today.year)
return DateTime(year,month,day,hour,minute,second)
else:
raise TypeError,'cannot convert arguments to DateTime'
def DateTimeDeltaFrom(*args, **kws):
""" DateTimeDeltaFrom(*args, **kws)
Generic DateTimeDelta instance constructor. Can handle parsing
strings, numbers and keywords.
XXX Add support for Unicode.
"""
if len(args) == 1:
# Single argument
arg = args[0]
if _isstring(arg):
import Parser
return apply(Parser.DateTimeDeltaFromString, args, kws)
elif type(arg) is DateTimeDeltaType:
return arg
elif type(arg) is DateTimeType:
raise TypeError,'cannot convert DateTime to DateTimeDelta'
else:
try:
value = float(arg)
except TypeError:
value = int(arg)
assert not kws
return DateTimeDeltaFromSeconds(value)
elif len(args) > 1:
# Assume the arguments are the same as for DateTimeDelta()
return apply(DateTimeDelta, args, kws)
elif len(kws) > 0:
# Keyword arguments; default: 00:00:00:00.00
hours = kws.get('hours',0)
minutes = kws.get('minutes',0)
seconds = kws.get('seconds',0.0)
days = kws.get('days',0)
return DateTimeDelta(days,hours,minutes,seconds)
else:
raise TypeError,'cannot convert arguments to DateTimeDelta'
def TimeDeltaFrom(*args, **kws):
""" TimeDeltaFrom(*args, **kws)
Generic TimeDelta instance constructor. Can handle parsing
strings, numbers and keywords.
XXX Add support for Unicode.
"""
if len(args) > 1:
# Assume the arguments are the same as for TimeDelta(): without
# days part !
return apply(DateTimeDelta, (0,)+args, kws)
else:
# Otherwise treat the arguments just like for DateTimeDelta
# instances.
return apply(DateTimeDeltaFrom, args, kws)
def DateFromTicks(ticks,
# Locals:
DateTime=DateTime,localtime=_time.localtime):
""" DateFromTicks(ticks)
Constructs a DateTime instance pointing to the local time date
at 00:00:00.00 (midnight) indicated by the given ticks value.
The time part is ignored.
"""
return apply(DateTime, localtime(ticks)[:3])
def TimestampFromTicks(ticks,
# Locals:
DateTime=DateTime,localtime=_time.localtime):
""" TimestampFromTicks(ticks)
Constructs a DateTime instance pointing to the local date and
time indicated by the given ticks value.
"""
return apply(DateTime, localtime(ticks)[:6])
def TimeFromTicks(ticks,
# Locals:
DateTimeDelta=DateTimeDelta,localtime=_time.localtime):
""" TimeFromTicks(ticks)
Constructs a DateTimeDelta instance pointing to the local time
indicated by the given ticks value. The date part is ignored.
"""
return apply(DateTimeDelta, (0,) + localtime(ticks)[3:6])
# Aliases
utctime = gmtime
utc2local = gm2local
local2utc = local2gm
DateTimeFromTicks = localtime
Date = DateTime
Time = TimeDelta
Timestamp = DateTime
DateFrom = DateTimeFrom # XXX should only parse the date part !
TimeFrom = TimeDeltaFrom
TimestampFrom = DateTimeFrom
GregorianDateTime = DateTime
GregorianDate = Date
JulianDate = JulianDateTime
### For backward compatibility (these are depreciated):
def gmticks(datetime):
"""gmticks(datetime)
[DEPRECIATED: use the .gmticks() method]
Returns a ticks value based on the values stored in
datetime under the assumption that they are given in UTC,
rather than local time.
"""
return datetime.gmticks()
# Alias
utcticks = gmticks
def tz_offset(datetime,
# Locals:
oneSecond=oneSecond):
"""tz_offset(datetime)
[DEPRECIATED: use the .gmtoffset() method]
Returns a DateTimeDelta instance representing the UTC
offset for datetime assuming that the stored values refer
to local time. If you subtract this value from datetime,
you'll get UTC time.
"""
return datetime.gmtoffset()
### Constants (only English; see Locale.py for other languages)
# Weekdays
Monday = 0
Tuesday = 1
Wednesday = 2
Thursday = 3
Friday = 4
Saturday = 5
Sunday = 6
# as mapping
Weekday = {'Saturday': 5, 6: 'Sunday', 'Sunday': 6, 'Thursday': 3,
'Wednesday': 2, 'Friday': 4, 'Tuesday': 1, 'Monday': 0,
5: 'Saturday', 4: 'Friday', 3: 'Thursday', 2: 'Wednesday',
1: 'Tuesday', 0: 'Monday'}
# Months
January = 1
February = 2
March = 3
April = 4
May = 5
June = 6
July = 7
August = 8
September = 9
October = 10
November = 11
December = 12
# as mapping
Month = {2: 'February', 3: 'March', None: 0, 'July': 7, 11: 'November',
'December': 12, 'June': 6, 'January': 1, 'September': 9, 'August':
8, 'March': 3, 'November': 11, 'April': 4, 12: 'December', 'May':
5, 10: 'October', 9: 'September', 8: 'August', 7: 'July', 6:
'June', 5: 'May', 4: 'April', 'October': 10, 'February': 2, 1:
'January', 0: None}
# Limits (see also the range checks in mxDateTime.c)
MaxDateTime = DateTime(5867440,12,31)
MinDateTime = DateTime(-5851455,1,1)
MaxDateTimeDelta = DateTimeDeltaFromSeconds(2147483647 * 86400.0)
MinDateTimeDelta = -MaxDateTimeDelta
###
class RelativeDateTime:
"""RelativeDateTime(years=0,months=0,days=0,
hours=0,minutes=0,seconds=0,
year=0,month=0,day=0,
hour=None,minute=None,second=None,
weekday=None,weeks=None)
Returns a RelativeDateTime instance for the specified relative
time. The constructor handles keywords, so you'll only have to
give those parameters which should be changed when you add the
relative to an absolute DateTime instance.
Adding RelativeDateTime instances is supported with the
following rules: deltas will be added together, right side
absolute values override left side ones.
Adding RelativeDateTime instances to DateTime instances will
return DateTime instances with the appropriate calculations
applied, e.g. to get a DateTime instance for the first of next
month, you'd call now() + RelativeDateTime(months=+1,day=1).
"""
years = 0
months = 0
days = 0
year = None
month = 0
day = 0
hours = 0
minutes = 0
seconds = 0
hour = None
minute = None
second = None
weekday = None
# cached hash value
_hash = None
# For Zope security:
__roles__ = None
__allow_access_to_unprotected_subobjects__ = 1
def __init__(self,
years=0,months=0,days=0,
hours=0,minutes=0,seconds=0,
year=None,month=None,day=None,
hour=None,minute=None,second=None,
weekday=None,weeks=0):
self.years = years
self.months = months
self.days = days + weeks*7
self.year = year
self.month = month
self.day = day
self.hours = hours
self.minutes = minutes
self.seconds = seconds
self.hour = hour
self.minute = minute
self.second = second
if weekday is not None:
# Make sure we've got a 2-tuple
assert len(weekday) == 2
self.weekday = weekday
def __add__(self,other,
# Locals:
isinstance=isinstance):
if isinstance(other,RelativeDateTime):
# RelativeDateTime (self) + RelativeDateTime (other)
r = RelativeDateTime()
# date deltas
r.years = self.years + other.years
r.months = self.months + other.months
r.days = self.days + other.days
# absolute entries of other override those in self, if given
r.year = other.year or self.year
r.month = other.month or self.month
r.day = other.day or self.day
r.weekday = other.weekday or self.weekday
# time deltas
r.hours = self.hours + other.hours
r.minutes = self.minutes + other.minutes
r.seconds = self.seconds + other.seconds
# absolute entries of other override those in self, if given
r.hour = other.hour or self.hour
r.minute = other.minute or self.minute
r.second = other.second or self.second
return r
else:
raise TypeError,"can't add the two types"
def __radd__(self,other,
# Locals:
isinstance=isinstance,DateTimeType=DateTimeType,
DateTime=DateTime,DateTimeDelta=DateTimeDelta):
if isinstance(other,DateTimeType):
# DateTime (other) + RelativeDateTime (self)
# date
if self.year is None:
year = other.year + self.years
else:
year = self.year + self.years
if self.month is None:
month = other.month + self.months
else:
month = self.month + self.months
if self.day is None:
day = other.day
else:
day = self.day
if day < 0:
# fix negative day values
month = month + 1
day = day + 1
day = day + self.days
# time
if self.hour is None:
hour = other.hour + self.hours
else:
hour = self.hour + self.hours
if self.minute is None:
minute = other.minute + self.minutes
else:
minute = self.minute + self.minutes
if self.second is None:
second = other.second + self.seconds
else:
second = self.second + self.seconds
# Refit into proper ranges:
if month < 1 or month > 12:
month = month - 1
yeardelta, monthdelta = divmod(month, 12)
year = year + yeardelta
month = monthdelta + 1
# Make sure we have integers
year = int(year)
month = int(month)
day = int(day)
if self.weekday is None:
return DateTime(year, month, 1) + \
DateTimeDelta(day-1,hour,minute,second)
# Adjust to the correct weekday
day_of_week,index = self.weekday
d = DateTime(year, month, 1) + \
DateTimeDelta(day-1,hour,minute,second)
if index == 0:
# 0 index: next weekday if no match
return d + (day_of_week - d.day_of_week)
elif index > 0:
# positive index (1 == first weekday of month)
first = d - (d.day - 1)
diff = day_of_week - first.day_of_week
if diff >= 0:
return first + (diff + (index-1) * 7)
else:
return first + (diff + index * 7)
else:
# negative index (-1 == last weekday of month)
last = d + (d.days_in_month - d.day)
diff = day_of_week - last.day_of_week
if diff <= 0:
return last + (diff + (index+1) * 7)
else:
return last + (diff + index * 7)
else:
raise TypeError,"can't add the two types"
def __sub__(self,other):
if isinstance(other,RelativeDateTime):
# RelativeDateTime (self) - RelativeDateTime (other)
r = RelativeDateTime()
# date deltas
r.years = self.years - other.years
r.months = self.months - other.months
r.days = self.days - other.days
# absolute entries of other override those in self, if given
r.year = other.year or self.year
r.month = other.month or self.month
r.day = other.day or self.day
r.weekday = other.weekday or self.weekday
# time deltas
r.hours = self.hours - other.hours
r.minutes = self.minutes - other.minutes
r.seconds = self.seconds - other.seconds
# absolute entries of other override those in self, if given
r.hour = other.hour or self.hour
r.minute = other.minute or self.minute
r.second = other.second or self.second
return r
else:
raise TypeError,"can't subtract the two types"
def __rsub__(self,other,
# Locals:
isinstance=isinstance,DateTimeType=DateTimeType):
if isinstance(other,DateTimeType):
# DateTime (other) - RelativeDateTime (self)
return other + self.__neg__()
else:
raise TypeError,"can't subtract the two types"
def __neg__(self):
# - RelativeDateTime(self)
r = RelativeDateTime()
# negate date deltas
r.years = - self.years
r.months = - self.months
r.days = - self.days
# absolute entries don't change
r.year = self.year
r.month = self.month
r.day = self.day
r.weekday = self.weekday
# negate time deltas
r.hours = - self.hours
r.minutes = - self.minutes
r.seconds = - self.seconds
# absolute entries don't change
r.hour = self.hour
r.minute = self.minute
r.second = self.second
return r
def __nonzero__(self):
# RelativeDateTime instances are considered false in case
# they do not define any alterations
if (self.year is None and
self.years == 0 and
self.month is None and
self.months == 0 and
self.day is None and
self.weekday is None and
self.days == 0 and
self.hour is None and
self.hours == 0 and
self.minute is None and
self.minutes == 0 and
self.second is None and
self.seconds == 0):
return 0
else:
return 1
def __mul__(self,other):
# RelativeDateTime (self) * Number (other)
factor = float(other)
r = RelativeDateTime()
# date deltas
r.years = factor * self.years
r.months = factor * self.months
r.days = factor * self.days
# time deltas
r.hours = factor * self.hours
r.minutes = factor * self.minutes
r.seconds = factor * self.seconds
return r
__rmul__ = __mul__
def __div__(self,other):
# RelativeDateTime (self) / Number (other)
return self.__mul__(1/float(other))
def __eq__(self, other):
if isinstance(self, RelativeDateTime) and \
isinstance(other, RelativeDateTime):
# RelativeDateTime (self) == RelativeDateTime (other)
if (self.years == other.years and
self.months == other.months and
self.days == other.days and
self.year == other.year and
self.day == other.day and
self.hours == other.hours and
self.minutes == other.minutes and
self.seconds == other.seconds and
self.hour == other.hour and
self.minute == other.minute and
self.second == other.second and
self.weekday == other.weekday):
return 1
else:
return 0
else:
raise TypeError,"can't compare the two types"
def __hash__(self):
if self._hash is not None:
return self._hash
x = 1234
for value in (self.years, self.months, self.days,
self.year, self.day,
self.hours, self.minutes, self.seconds,
self.hour, self.minute, self.second,
self.weekday):
if value is None:
x = 135051820 ^ x
else:
x = hash(value) ^ x
self._hash = x
return x
def __str__(self,
join=_string.join):
l = []
append = l.append
# Format date part
if self.year is not None:
append('%04i-' % self.year)
elif self.years:
append('(%0+5i)-' % self.years)
else:
append('YYYY-')
if self.month is not None:
append('%02i-' % self.month)
elif self.months:
append('(%0+3i)-' % self.months)
else:
append('MM-')
if self.day is not None:
append('%02i' % self.day)
elif self.days:
append('(%0+3i)' % self.days)
else:
append('DD')
if self.weekday:
append(' %s:%i' % (Weekday[self.weekday[0]][:3],self.weekday[1]))
append(' ')
# Normalize relative time values to avoid fractions
hours = self.hours
minutes = self.minutes
seconds = self.seconds
hours_fraction = hours - int(hours)
minutes = minutes + hours_fraction * 60.0
minutes_fraction = minutes - int(minutes)
seconds = seconds + minutes_fraction * 6.0
seconds_fraction = seconds - int(seconds)
if 0:
# Normalize to standard time ranges
if seconds > 60.0:
extra_minutes, seconds = divmod(seconds, 60.0)
minutes = minutes + extra_minutes
elif seconds < -60.0:
extra_minutes, seconds = divmod(seconds, -60.0)
minutes = minutes - extra_minutes
if minutes >= 60.0:
extra_hours, minutes = divmod(minutes, 60.0)
hours = hours + extra_hours
elif minutes <= -60.0:
extra_hours, minutes = divmod(minutes, -60.0)
hours = hours - extra_hours
# Format time part
if self.hour is not None:
append('%02i:' % self.hour)
elif hours:
append('(%0+3i):' % hours)
else:
append('HH:')
if self.minute is not None:
append('%02i:' % self.minute)
elif minutes:
append('(%0+3i):' % minutes)
else:
append('MM:')
if self.second is not None:
append('%02i' % self.second)
elif seconds:
append('(%0+3i)' % seconds)
else:
append('SS')
return join(l,'')
def __repr__(self):
return "<%s instance for '%s' at 0x%x>" % (
self.__class__.__name__,
self.__str__(),
id(self))
# Alias
RelativeDate = RelativeDateTime
def RelativeDateTimeFrom(*args, **kws):
""" RelativeDateTimeFrom(*args, **kws)
Generic RelativeDateTime instance constructor. Can handle
parsing strings and keywords.
"""
if len(args) == 1:
# Single argument
arg = args[0]
if _isstring(arg):
import Parser
return apply(Parser.RelativeDateTimeFromString, args, kws)
elif isinstance(arg, RelativeDateTime):
return arg
else:
raise TypeError,\
'cannot convert argument to RelativeDateTime'
else:
return apply(RelativeDateTime,args,kws)
def RelativeDateTimeDiff(date1,date2,
floor=_math.floor,int=int,divmod=divmod,
RelativeDateTime=RelativeDateTime):
""" RelativeDateTimeDiff(date1,date2)
Returns a RelativeDateTime instance representing the difference
between date1 and date2 in relative terms.
The following should hold:
date2 + RelativeDateDiff(date1,date2) == date1
for all dates date1 and date2.
Note that due to the algorithm used by this function, not the
whole range of DateTime instances is supported; there could
also be a loss of precision.
XXX There are still some problems left (thanks to Carel
Fellinger for pointing these out):
29 1 1901 -> 1 3 1901 = 1 month
29 1 1901 -> 1 3 1900 = -10 month and -28 days, but
29 1 1901 -> 28 2 1900 = -11 month and -1 day
and even worse:
>>> print RelativeDateDiff(Date(1900,3,1),Date(1901,2,1))
YYYY-(-11)-DD HH:MM:SS
with:
>>> print Date(1901,1,29) + RelativeDateTime(months=-11)
1900-03-01 00:00:00.00
>>> print Date(1901,2,1) + RelativeDateTime(months=-11)
1900-03-01 00:00:00.00
"""
diff = date1 - date2
if diff.days == 0:
return RelativeDateTime()
date1months = date1.year * 12 + (date1.month - 1)
date2months = date2.year * 12 + (date2.month - 1)
#print 'months',date1months,date2months
# Calculate the months difference
diffmonths = date1months - date2months
#print 'diffmonths',diffmonths
if diff.days > 0:
years,months = divmod(diffmonths,12)
else:
years,months = divmod(diffmonths,-12)
years = -years
date3 = date2 + RelativeDateTime(years=years,months=months)
diff3 = date1 - date3
days = date1.absdays - date3.absdays
#print 'date3',date3,'diff3',diff3,'days',days
# Correction to ensure that all relative parts have the same sign
while days * diff.days < 0:
if diff.days > 0:
diffmonths = diffmonths - 1
years,months = divmod(diffmonths,12)
else:
diffmonths = diffmonths + 1
years,months = divmod(diffmonths,-12)
years = -years
#print 'diffmonths',diffmonths
date3 = date2 + RelativeDateTime(years=years,months=months)
diff3 = date1 - date3
days = date1.absdays - date3.absdays
#print 'date3',date3,'diff3',diff3,'days',days
# Drop the fraction part of days
if days > 0:
days = int(floor(days))
else:
days = int(-floor(-days))
return RelativeDateTime(years=years,
months=months,
days=days,
hours=diff3.hour,
minutes=diff3.minute,
seconds=diff3.second)
# Aliases
RelativeDateDiff = RelativeDateTimeDiff
Age = RelativeDateTimeDiff
###
_current_year = now().year
_current_century, _current_year_in_century = divmod(_current_year, 100)
_current_century = _current_century * 100
def add_century(year,
current_year=_current_year,
current_century=_current_century):
""" Sliding window approach to the Y2K problem: adds a suitable
century to the given year and returns it as integer.
The window used depends on the current year (at import time).
If adding the current century to the given year gives a year
within the range current_year-70...current_year+30 [both
inclusive], then the current century is added. Otherwise the
century (current + 1 or - 1) producing the least difference is
chosen.
"""
if year > 99:
# Take it as-is
return year
year = year + current_century
diff = year - current_year
if diff >= -70 and diff <= 30:
return year
elif diff < -70:
return year + 100
else:
return year - 100
# Reference formulas for JDN taken from the Calendar FAQ:
def gregorian_jdn(year,month,day):
# XXX These require proper integer division.
a = (14-month)/12
y = year+4800-a
m = month + 12*a - 3
return day + (306*m+5)/10 + y*365 + y/4 - y/100 + y/400 - 32045
def julian_jdn(year,month,day):
# XXX These require proper integer division.
a = (14-month)/12
y = year+4800-a
m = month + 12*a - 3
return day + (306*m+5)/10 + y*365 + y/4 - 32083