在Python中计算两个日期时间之间的工作日差异？

Question

这个问题和计算两个日期之间的天数差（不算周末）是一样的，不过这是关于JavaScript的。那在Python中怎么做呢？

Answer 1

我不确定这是不是最好的解决办法，但对我来说有效：

from datetime import datetime, timedelta

startDate = datetime(2011, 7, 7)
endDate = datetime(2011, 10, 7)
dayDelta = timedelta(days=1)
diff = 0
while startDate != endDate:
    if startDate.weekday() not in [5,6]:
        diff += 1
    startDate += dayDelta

Answer 2

这里有一个复杂度为O(1)的解决方案，它只使用了Python自带的库。

这个方案的表现是恒定的，不管时间间隔的长度如何，也不在乎参数的顺序。

#
# by default, the last date is not inclusive
#
def workdaycount(first, second, inc = 0):
   if first == second:
      return 0
   import math
   if first > second:
      first, second = second, first
   if inc:
      from datetime import timedelta
      second += timedelta(days=1)
   interval = (second - first).days
   weekspan = int(math.ceil(interval / 7.0))
   if interval % 7 == 0:
      return interval - weekspan * 2
   else:
      wdf = first.weekday()
      if (wdf < 6) and ((interval + wdf) // 7 == weekspan):
         modifier = 0
      elif (wdf == 6) or ((interval + wdf + 1) // 7 == weekspan):
         modifier = 1
      else:
         modifier = 2
      return interval - (2 * weekspan - modifier)

#
# sample usage
#
print workdaycount(date(2011, 8, 15), date(2011, 8, 22)) # returns 5
print workdaycount(date(2011, 8, 15), date(2011, 8, 22), 1) # last date inclusive, returns 6

Answer 3

可以试试这个 scikits.timeseries：

import scikits.timeseries as ts
import datetime

a = datetime.datetime(2011,8,1)
b = datetime.datetime(2011,8,29)

diff_business_days = ts.Date('B', b) - ts.Date('B', a)
# returns 20

或者用这个 dateutil：

import datetime
from dateutil import rrule

a = datetime.datetime(2011,8,1)
b = datetime.datetime(2011,8,29)

diff_business_days = len(list(rrule.rrule(rrule.DAILY,
                                          dtstart=a,
                                          until=b - datetime.timedelta(days=1),
                                          byweekday=(rrule.MO, rrule.TU, rrule.WE, rrule.TH, rrule.FR))))

---

scikits.timeseries 看起来已经不再维护了：http://pytseries.sourceforge.net/

如果用 pandas，大家可以这样做：

import pandas as pd

a = datetime.datetime(2015, 10, 1)
b = datetime.datetime(2015, 10, 29)

diff_calendar_days = pd.date_range(a, b).size
diff_business_days = pd.bdate_range(a, b).size