Question

正如我现在在python中所理解的那样，没有功能可以从当前日期的gps纪元获得闰秒。正在调查/开发的适当补丁：leap seconds path in datetime

你能建议如何获得闰秒的最佳方法吗？我找到了解决方案：

def getLeapSec(Tgps):
  daysFromGPSEpoch = timedelta(seconds=Tgps).days
  tableLeapSec = ([
    [0,  542,  907, 1272, 2003, 2917, 3648, 4013, 4560, 4925, 5290, 5839, 6386, 6935, 9492, 10588, 11865, 12960],
    [0,    1,    2,    3,    4,    5,    6,    7,    8,    9,   10,   11,   12,   13,   14,    15,    16,    17]
                 ])

  for i in range(1, len(tableLeapSec[0])):
    if daysFromGPSEpoch < tableLeapSec[0][i]:
      return tableLeapSec[1][i-1]

示例：

In [25]: Tgps = 1092121243.0

In [26]: getLeapSec(Tgps)
Out[26]: 16

Answer 1

You could use leapseconds module if you have access to the up-to-date tzfile on your system:

>>> from datetime import datetime, timedelta
>>> import leapseconds
>>> Tgps = 1092121243.0
>>> gps_time = datetime(1980, 1, 6) + timedelta(seconds=Tgps)
>>> leapseconds.dTAI_UTC_from_tai(leapseconds.gps_to_tai(gps_time))
datetime.timedelta(0, 35)

The main advantage is that tzdata package is updated several times per year by the system automatically (more often than leap seconds are introduced). Your code will use the new data without the need to change it.

Otherwise, as a fallback, you could hardcode the result of the leapseconds.leapseconds() call:

>>> import leapseconds
>>> leapseconds.leapseconds()
[LeapSecond(utc=datetime.datetime(1972, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 10)),
 LeapSecond(utc=datetime.datetime(1972, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 11)),
 LeapSecond(utc=datetime.datetime(1973, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 12)),
 LeapSecond(utc=datetime.datetime(1974, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 13)),
 LeapSecond(utc=datetime.datetime(1975, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 14)),
 LeapSecond(utc=datetime.datetime(1976, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 15)),
 LeapSecond(utc=datetime.datetime(1977, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 16)),
 LeapSecond(utc=datetime.datetime(1978, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 17)),
 LeapSecond(utc=datetime.datetime(1979, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 18)),
 LeapSecond(utc=datetime.datetime(1980, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 19)),
 LeapSecond(utc=datetime.datetime(1981, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 20)),
 LeapSecond(utc=datetime.datetime(1982, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 21)),
 LeapSecond(utc=datetime.datetime(1983, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 22)),
 LeapSecond(utc=datetime.datetime(1985, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 23)),
 LeapSecond(utc=datetime.datetime(1988, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 24)),
 LeapSecond(utc=datetime.datetime(1990, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 25)),
 LeapSecond(utc=datetime.datetime(1991, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 26)),
 LeapSecond(utc=datetime.datetime(1992, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 27)),
 LeapSecond(utc=datetime.datetime(1993, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 28)),
 LeapSecond(utc=datetime.datetime(1994, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 29)),
 LeapSecond(utc=datetime.datetime(1996, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 30)),
 LeapSecond(utc=datetime.datetime(1997, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 31)),
 LeapSecond(utc=datetime.datetime(1999, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 32)),
 LeapSecond(utc=datetime.datetime(2006, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 33)),
 LeapSecond(utc=datetime.datetime(2009, 1, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 34)),
 LeapSecond(utc=datetime.datetime(2012, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 35)),
 LeapSecond(utc=datetime.datetime(2015, 7, 1, 0, 0), dTAI_UTC=datetime.timedelta(0, 36))]

You have to update the list manually when the next leap second is introduced in this case.

The authoritative source for the leap seconds updates is Bulletin C issued by IERS that also provides TAI-UTC data since 1961.

You could ping IESR once in a half-year (e.g., January, July), to find out programmatically using leap_second_client.py when the next leap second is scheduled.

如何在python中获取当前日期的gps epoch的闰秒

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