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Python日期时间字段_Python_Pandas_Datetime - Fatal编程技术网

Python日期时间字段

Python日期时间字段,python,pandas,datetime,Python,Pandas,Datetime,请参阅此程序: dfPeople = pd.DataFrame({'name': ['alice','bob'],'date_of_birth': ['10/25/1995 03:30','10/29/2002 9:25']}) dfPeople['date_of_birth'] = pd.to_datetime(dfPeople['date_of_birth']) dfPeople['date_of_birth'].dtype theDate = dfPeople['date_of_b

请参阅此程序:

dfPeople = pd.DataFrame({'name': ['alice','bob'],'date_of_birth': ['10/25/1995 03:30','10/29/2002 9:25']})

dfPeople['date_of_birth'] = pd.to_datetime(dfPeople['date_of_birth'])

dfPeople['date_of_birth'].dtype 

theDate = dfPeople['date_of_birth'].dt.date
日期应该提取日期。当我尝试这样的事情时

if theDate[0]=='1995-10-25':
    print("equal")

我没有看到打印的声明。提前谢谢。

这是意料之中的,因为比较类型
日期
和类型
字符串

因此,我们需要:

from datetime import datetime

if theDate[0]==datetime.strptime('1995-10-25', '%Y-%m-%d').date():
     print("equal")
如果希望在pandas中比较掩码,则可以使用或删除时间,但仍然是日期时间,因此请使用字符串进行比较:

theDate = dfPeople['date_of_birth'].dt.floor('d')
#alternative
#theDate = dfPeople['date_of_birth'].dt.normalize()
print (theDate == '1995-10-25')   
0     True
1    False
Name: date_of_birth, dtype: bool

因为比较类型
date
和类型
string
,所以应该是这样

因此,我们需要:

from datetime import datetime

if theDate[0]==datetime.strptime('1995-10-25', '%Y-%m-%d').date():
     print("equal")
如果希望在pandas中比较掩码,则可以使用或删除时间,但仍然是日期时间,因此请使用字符串进行比较:

theDate = dfPeople['date_of_birth'].dt.floor('d')
#alternative
#theDate = dfPeople['date_of_birth'].dt.normalize()
print (theDate == '1995-10-25')   
0     True
1    False
Name: date_of_birth, dtype: bool