如何将字符串转换为日期 Pandas python TypeError：strptime() 不接受关键字参数
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/22138932/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
how to convert string to date pandas python TypeError: strptime() takes no keyword arguments
提问by yoshiserry
I have a dataframe with some text dates in them. I would like to return the dates: year, month and day in separate columns. But in order to do that I need to first convert the text(from excel) to a date.
我有一个包含一些文本日期的数据框。我想在单独的列中返回日期：年、月和日。但是为了做到这一点，我需要首先将文本（从 excel）转换为日期。
The code I have now is
我现在的代码是
def convertdate(dstring):
dt = time.strptime(dstring, date_format='%Y-%m-%d')
return dt
However it returns an: TypeError: strptime() takes no keyword arguments
但是它返回一个： TypeError: strptime() takes no keyword arguments
Then instead of three separate functions for creating three separate columns, one for year, one for month, one for day.
然后，而不是用于创建三个单独列的三个单独的函数，一个用于年，一个用于月，一个用于日。
Once the string is a date time object (dt), I believe the code is: return dt.year, return dt.month, return dt.day.
一旦字符串是日期时间对象（dt），我相信代码是：return dt.year, return dt.month, return dt.day.
I would like one function which adds three columns to my dataframe, is this possible?
我想要一个向我的数据框添加三列的函数，这可能吗？
回答by falsetru
Pass the format string as a positional argument.
将格式字符串作为位置参数传递。
>>> import time
>>> def convertdate(dstring):
... return time.strptime(dstring, '%Y-%m-%d')
...
>>> convertdate('2013-03-02')
time.struct_time(tm_year=2013, tm_mon=3, tm_mday=2, tm_hour=0, tm_min=0, tm_sec=0, tm_wday=5, tm_yday=61, tm_isdst=-1)
BTW, time.strptimereturns time.struct_time. Its attributes are prefixed with tm_.
顺便说一句，time.strptime返回time.struct_time。它的属性以 为前缀tm_。
More preferably you can use datetime.datetime.strptime:
更优选地，您可以使用datetime.datetime.strptime：
>>> import datetime
>>> import pandas as pd
>>>
>>> def convertdate(dstring):
... return datetime.datetime.strptime(dstring, '%Y-%m-%d')
...
>>> dt = convertdate('2013-03-02')
>>> dt
datetime.datetime(2013, 3, 2, 0, 0)
>>> pd.DataFrame([{'year': dt.year, 'month': dt.month, 'day': dt.day}])
day month year
0 2 3 2013
