Following this answer I tried to get the date for last Thursday of the current month. But my code doesn't get out of loop.
from datetime import datetime
from dateutil.relativedelta import relativedelta, TH
todayte = datetime.today()
cmon = todayte.month
nthu = todayte
while nthu.month == cmon:
nthu += relativedelta(weekday=TH(1))
#print nthu.strftime('%d%b%Y').upper()
Looking at the documentation of relativedelta
Notice that if the calculated date is already
Monday, for example, using(0, 1)or(0, -1)won’t change the day.
If nthu is already Thursday then adding TH(1) or TH(-1) won't have any effect but result in the same date and that's why your loop is running infinitely.
I will assume maximum 5 weeks in a month and do it like following:
todayte = datetime.today()
cmon = todayte.month
for i in range(1, 6):
t = todayte + relativedelta(weekday=TH(i))
if t.month != cmon:
# since t is exceeded we need last one which we can get by subtracting -2 since it is already a Thursday.
t = t + relativedelta(weekday=TH(-2))
break
Based on Adam Smith's answer on How can I get the 3rd Friday of a month in Python?, you can get the date of the last Thursday of the current month as follows:
import calendar
import datetime
def get_thursday(cal,year,month,thursday_number):
'''
For example, get_thursday(cal, 2017,8,0) returns (2017,8,3)
because the first thursday of August 2017 is 2017-08-03
'''
monthcal = cal.monthdatescalendar(year, month)
selected_thursday = [day for week in monthcal for day in week if \
day.weekday() == calendar.THURSDAY and \
day.month == month][thursday_number]
return selected_thursday
def main():
'''
Show the use of get_thursday()
'''
cal = calendar.Calendar(firstweekday=calendar.MONDAY)
today = datetime.datetime.today()
year = today.year
month = today.month
date = get_thursday(cal,year,month,-1) # -1 because we want the last Thursday
print('date: {0}'.format(date)) # date: 2017-08-31
if __name__ == "__main__":
main()
You can do something like this:
import pandas as pd
from dateutil.relativedelta import relativedelta, TH
expiry_type = 0
today = pd.datetime.today()
expiry_dates = []
if expiry_type == 0:
# Weekly expiry
for i in range(1,13):
expiry_dates.append((today + relativedelta(weekday=TH(i))).date())
else:
# Monthly expiry
for i in range(1,13):
x = (today + relativedelta(weekday=TH(i))).date()
y = (today + relativedelta(weekday=TH(i+1))).date()
if x.month != y.month :
if x.day > y.day :
expiry_dates.append(x)
print(expiry_dates)
You should pass 2 to TH instead of 1, as 1 doesn't change anything. Modify your code to:
while (nthu + relativedelta(weekday=TH(2))).month == cmon:
nthu += relativedelta(weekday=TH(2))
print nthu.strftime('%d-%b-%Y').upper()
# prints 26-MAY-2016
Note that I modified the loop's condition in order to break in the last occurrence of the day on the month, otherwise it'll break in the next month (in this case, June).
from datetime import datetime , timedelta
todayte = datetime.today()
cmon = todayte.month
nthu = todayte
while todayte.month == cmon:
todayte += timedelta(days=1)
if todayte.weekday()==3: #this is Thursday
nthu = todayte
print nthu
You can also use calendar package.
Access the calendar in the form of monthcalendar. and notice that, the Friday is the last day of a week.
import calendar
import datetime
now = datetime.datetime.now()
last_sunday = max(week[-1] for week in calendar.monthcalendar(now.year,
now.month))
print('{}-{}-{:2}'.format(now.year, calendar.month_abbr[now.month],
last_sunday))
I think this will be fastest perhaps:
end_of_month = datetime.datetime.today() + relativedelta(day=31)
last_thursday = end_of_month + relativedelta(weekday=TH(-1))
This code can be used in python 3.x for finding last Thursday of current month.
import datetime
dt = datetime.datetime.today()
def lastThurs(dt):
currDate, currMth, currYr = dt, dt.month, dt.year
for i in range(31):
if currDate.month == currMth and currDate.year == currYr and currDate.weekday() == 3:
#print('dt:'+ str(currDate))
lastThuDate = currDate
currDate += datetime.timedelta(1)
return lastThuDate
import datetime
def get_thursday(_month,_year):
for _i in range(1,32):
if _i > 9:
_dateStr = str(_i)
else:
_dateStr = '0' + str(_i)
_date = str(_year) + '-' + str(_month) + '-' + _dateStr
try:
a = datetime.datetime.strptime(_date, "%Y-%m-%d").strftime('%a')
except:
continue
if a == 'Thu':
_lastThurs = _date
return _lastThurs
x = get_thursday('05','2017')
print(x)
It is straightforward fast and easy to understand, we take the first of every month and then subtract it by 3 coz 3 is Thursday weekday number and then multiply it by either 4 and check if it is in the same month if it is then that is last Thursday otherwise we multiply it with 3 and we get our last Thursday
import datetime as dt
from datetime import timedelta
#start is the first of every month
start = dt.datetime.fromisoformat('2022-08-01')
if start.month == (start + timedelta((3 - start.weekday()) + 4*7)).month:
exp = start + timedelta((3 - start.weekday()) + 4*7)
else:
exp = start + timedelta((3 - start.weekday()) + 3*7)
You can use Calendar to achieve your result. I find it simple.
import calendar
import datetime
testdate= datetime.datetime.now()
weekly_thursday=[]
for week in calendar.monthcalendar(testdate.year,testdate.month):
if week[3] != 0:
weekly_thursday.append(week[3])
weekly_thursday
The list weekly_thursday will have all the Thursdays from the month.
weekly_thursday[-1] will give you the last Thursday of the month.
testdate : datetime.datetime(2022, 9, 9, 6, 35, 16, 752465)
weekly_thursday : [1, 8, 15, 22, 29]
weekly_thursday [-1]:29
