我正在处理Python中的日期,我需要将它们转换为UTC时间戳以供使用
在Javascript。下面的代码不能工作:
>>> d = datetime.date(2011,01,01)
>>> datetime.datetime.utcfromtimestamp(time.mktime(d.timetuple()))
datetime.datetime(2010, 12, 31, 23, 0)
首先将date对象转换为datetime也没有帮助。我在这个链接中尝试了这个例子,但是:
from pytz import utc, timezone
from datetime import datetime
from time import mktime
input_date = datetime(year=2011, month=1, day=15)
现在:
mktime(utc.localize(input_date).utctimetuple())
or
mktime(timezone('US/Eastern').localize(input_date).utctimetuple())
做的工作。
一般问题:如何根据UTC将日期转换为从epoch开始的秒数?
一个完整的时间字符串包含:
日期
时间
utcoffset [+HHMM或-HHMM]
例如:
0000 == UNIX时间戳:3600
$ python3
>>> from datetime import datetime
>>> from calendar import timegm
>>> tm = '1970-01-01 06:00:00 +0500'
>>> fmt = '%Y-%m-%d %H:%M:%S %z'
>>> timegm(datetime.strptime(tm, fmt).utctimetuple())
3600
注意:
UNIX时间戳是一个浮点数,以UTC标准从epoch开始的秒数表示。
编辑:
$ python3
>>> from datetime import datetime, timezone, timedelta
>>> from calendar import timegm
>>> dt = datetime(1970, 1, 1, 6, 0)
>>> tz = timezone(timedelta(hours=5))
>>> timegm(dt.replace(tzinfo=tz).utctimetuple())
3600
这个问题有点混乱。时间戳不是UTC -它们是Unix的东西。日期可能是UTC?假设它是,并且如果你使用的是Python 3.2+,那么simple-date使这个问题变得微不足道:
>>> SimpleDate(date(2011,1,1), tz='utc').timestamp
1293840000.0
如果你有年、月和日,你不需要创建日期:
>>> SimpleDate(2011,1,1, tz='utc').timestamp
1293840000.0
如果日期在其他时区(这很重要,因为我们假设是午夜,没有相关的时间):
>>> SimpleDate(date(2011,1,1), tz='America/New_York').timestamp
1293858000.0
[simple-date背后的想法是将所有python的日期和时间收集到一个一致的类中,这样你就可以进行任何转换。例如,它也会向另一个方向发展:
>>> SimpleDate(1293858000, tz='utc').date
datetime.date(2011, 1, 1)
]
Assumption 1: You're attempting to convert a date to a timestamp, however since a date covers a 24 hour period, there isn't a single timestamp that represents that date. I'll assume that you want to represent the timestamp of that date at midnight (00:00:00.000).
Assumption 2: The date you present is not associated with a particular time zone, however you want to determine the offset from a particular time zone (UTC). Without knowing the time zone the date is in, it isn't possible to calculate a timestamp for a specific time zone. I'll assume that you want to treat the date as if it is in the local system time zone.
首先,您可以使用timetuple()成员将日期实例转换为表示各种时间组件的元组:
dtt = d.timetuple() # time.struct_time(tm_year=2011, tm_mon=1, tm_mday=1, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=5, tm_yday=1, tm_isdst=-1)
然后你可以使用time.mktime将其转换为时间戳:
ts = time.mktime(dtt) # 1293868800.0
您可以通过使用epoch时间本身(1970-01-01)测试来验证此方法,在这种情况下,函数应该返回该日期本地时区的时区偏移量:
d = datetime.date(1970,1,1)
dtt = d.timetuple() # time.struct_time(tm_year=1970, tm_mon=1, tm_mday=1, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=3, tm_yday=1, tm_isdst=-1)
ts = time.mktime(dtt) # 28800.0
28800.0是8小时,这对太平洋时区(我所在的时区)来说是正确的。