计算每月的最后一个星期五在熊猫
问题描述:
我已编写此函数来获取该月的最后一个星期四
I've written this function to get the last Thursday of the month
def last_thurs_date(date):
month=date.dt.month
year=date.dt.year
cal = calendar.monthcalendar(year, month)
last_thurs_date = cal[4][4]
if month < 10:
thurday_date = str(year)+'-0'+ str(month)+'-' + str(last_thurs_date)
else:
thurday_date = str(year) + '-' + str(month) + '-' + str(last_thurs_date)
return thurday_date
但它不起作用
datelist['Date'].map(lambda x: last_thurs_date(x))
日期列表在哪里
datelist = pd.DataFrame(pd.date_range(start = pd.to_datetime('01-01-2014',format='%d-%m-%Y')
, end = pd.to_datetime('06-03-2019',format='%d-%m-%Y'),freq='D').tolist()).rename(columns={0:'Date'})
datelist['Date']=pd.to_datetime(datelist['Date'])
答
Jpp已添加解决方案,但只是添加了更具可读性的格式化字符串-请参见很棒的网站。
Jpp already added the solution, but just to add a slightly more readable formatted string - see this awesome website.
import calendar
def last_thurs_date(date):
year, month = date.year, date.month
cal = calendar.monthcalendar(year, month)
# the last (4th week -> row) thursday (4th day -> column) of the calendar
# except when 0, then take the 3rd week (February exception)
last_thurs_date = cal[4][4] if cal[4][4] > 0 else cal[3][4]
return f'{year}-{month:02d}-{last_thurs_date}'
还添加了一些逻辑-例如您获得了 2019-02-0
,因为二月没有整整4周。
Also added a bit of logic - e.g. you got 2019-02-0
as February doesn't have 4 full weeks.