我正在尝试将 n (整数)个工作日添加到给定日期,日期添加必须避免假期和周末(它不包括在工作日中)
12 回答
跳过周末会很容易做这样的事情:
import datetime
def date_by_adding_business_days(from_date, add_days):
business_days_to_add = add_days
current_date = from_date
while business_days_to_add > 0:
current_date += datetime.timedelta(days=1)
weekday = current_date.weekday()
if weekday >= 5: # sunday = 6
continue
business_days_to_add -= 1
return current_date
#demo:
print '10 business days from today:'
print date_by_adding_business_days(datetime.date.today(), 10)
假期的问题在于,它们因国家甚至地区、宗教等而有很大差异。您需要为您的用例提供一个假期列表/一组,然后以类似的方式跳过它们。起点可能是 Apple 为 iCal 发布的日历提要(以 ics 格式),美国的日历提要是http://files.apple.com/calendars/US32Holidays.ics
您可以使用icalendar模块来解析它。
如果您不介意使用 3rd 方库,那么dateutil很方便
from dateutil.rrule import *
print "In 4 business days, it's", rrule(DAILY, byweekday=(MO,TU,WE,TH,FR))[4]
您还可以查看rruleset
并使用.exdate()
来提供假期以跳过计算中的假期,并且可以cache
选择避免重新计算的选项可能值得研究。
没有真正的捷径可以做到这一点。试试这个方法:
- 创建一个类,该类具有
skip(self, d)
返回True
应跳过的日期的方法。 - 在包含所有假期作为日期对象的类中创建一个字典。不要使用
datetime
或类似的,因为一天的一小部分会杀死你。 - 返回
True
字典中的任何日期或d.weekday() >= 5
要添加 N 天,请使用以下方法:
def advance(d, days):
delta = datetime.timedelta(1)
for x in range(days):
d = d + delta
while holidayHelper.skip(d):
d = d + delta
return d
感谢基于 omz 代码我做了一些小改动......它可能对其他用户有帮助:
import datetime
def date_by_adding_business_days(from_date, add_days,holidays):
business_days_to_add = add_days
current_date = from_date
while business_days_to_add > 0:
current_date += datetime.timedelta(days=1)
weekday = current_date.weekday()
if weekday >= 5: # sunday = 6
continue
if current_date in holidays:
continue
business_days_to_add -= 1
return current_date
#demo:
Holidays =[datetime.datetime(2012,10,3),datetime.datetime(2012,10,4)]
print date_by_adding_business_days(datetime.datetime(2012,10,2), 10,Holidays)
我想要一个不是 O(N) 的解决方案,它看起来像是一个有趣的代码高尔夫。这是我敲出来的,以防有人感兴趣。适用于正数和负数。如果我错过了什么,请告诉我。
def add_business_days(d, business_days_to_add):
num_whole_weeks = business_days_to_add / 5
extra_days = num_whole_weeks * 2
first_weekday = d.weekday()
remainder_days = business_days_to_add % 5
natural_day = first_weekday + remainder_days
if natural_day > 4:
if first_weekday == 5:
extra_days += 1
elif first_weekday != 6:
extra_days += 2
return d + timedelta(business_days_to_add + extra_days)
这将需要一些工作,因为在任何图书馆中都没有任何定义的假期结构(至少据我所知)。您将需要创建自己的枚举。
.weekday() < 6
通过调用您的 datetime 对象可以轻松地检查周末天数。
我知道它不处理假期,但我发现这个解决方案更有帮助,因为它在时间上是恒定的。它包括计算整周的数量,添加假期有点复杂。我希望它可以帮助某人:)
def add_days(days):
today = datetime.date.today()
weekday = today.weekday() + ceil(days)
complete_weeks = weekday // 7
added_days = weekday + complete_weeks * 2
return today + datetime.timedelta(days=added_days)
希望这可以帮助。不是O(N)
但是O(holidays)
。此外,假期仅在偏移量为正时有效。
def add_working_days(start, working_days, holidays=()):
"""
Add working_days to start start date , skipping weekends and holidays.
:param start: the date to start from
:type start: datetime.datetime|datetime.date
:param working_days: offset in working days you want to add (can be negative)
:type working_days: int
:param holidays: iterator of datetime.datetime of datetime.date instances
:type holidays: iter(datetime.date|datetime.datetime)
:return: the new date wroking_days date from now
:rtype: datetime.datetime
:raise:
ValueError if working_days < 0 and holidays
"""
assert isinstance(start, (datetime.date, datetime.datetime)), 'start should be a datetime instance'
assert isinstance(working_days, int)
if working_days < 0 and holidays:
raise ValueError('Holidays and a negative offset is not implemented. ')
if working_days == 0:
return start
# first just add the days
new_date = start + datetime.timedelta(working_days)
# now compensate for the weekends.
# the days is 2 times plus the amount of weeks are included in the offset added to the day of the week
# from the start. This compensates for adding 1 to a friday because 4+1 // 5 = 1
new_date += datetime.timedelta(2 * ((working_days + start.weekday()) // 5))
# now compensate for the holidays
# process only the relevant dates so order the list and abort the handling when the holiday is no longer
# relevant. Check each holiday not being in a weekend, otherwise we don't mind because we skip them anyway
# next, if a holiday is found, just add 1 to the date, using the add_working_days function to compensate for
# weekends. Don't pass the holiday to avoid recursion more then 1 call deep.
for hday in sorted(holidays):
if hday < start:
# ignore holidays before start, we don't care
continue
if hday.weekday() > 4:
# skip holidays in weekends
continue
if hday <= new_date:
# only work with holidays up to and including the current new_date.
# increment using recursion to compensate for weekends
new_date = add_working_days(new_date, 1)
else:
break
return new_date
如果有人需要添加/减去天数,请扩展@omz 的答案:
def add_business_days(from_date, ndays):
business_days_to_add = abs(ndays)
current_date = from_date
sign = ndays/abs(ndays)
while business_days_to_add > 0:
current_date += datetime.timedelta(sign * 1)
weekday = current_date.weekday()
if weekday >= 5: # sunday = 6
continue
business_days_to_add -= 1
return current_date
类似于@omz 解决方案,但递归:
def add_days_skipping_weekends(start_date, days):
if not days:
return start_date
start_date += timedelta(days=1)
if start_date.weekday() < 5:
days -= 1
return add_days_skipping_weekends(start_date, days)
如果您对使用 NumPy 感兴趣,那么您可以按照以下解决方案进行操作:
import numpy as np
from datetime import datetime, timedelta
def get_future_date_excluding_weekends(date,no_of_days):
"""This methods return future date by adding given number of days excluding
weekends"""
future_date = date + timedelta(no_of_days)
no_of_busy_days = int(np.busday_count(date.date(),future_date.date()))
if no_of_busy_days != no_of_days:
extend_future_date_by = no_of_days - no_of_busy_days
future_date = future_date + timedelta(extend_future_date_by)
return future_date
我正在使用以下代码来处理业务日期增量。对于假期,您需要创建自己的列表以跳过。
today = datetime.now()
t_1 = today - BDay(1)
t_5 = today - BDay(5)
t_1_str = datetime.strftime(t_1,"%Y%m%d")