字段“现在”,“结束日期”和“创建日期”是日期。使用EndDate / CreateDate的最新日期,“ diff_m”输出该字段与“现在”(向下取整)之间的月份差。
now=dt.now()
df['MaxDate'] = df[['EndDate', 'CreateDate']].max(axis=1)
df['diff_months'] = now - df['MaxDate']
df['diff_months']=df['diff_months']/np.timedelta64(1,'M')
df['diff_m']=df['diff_months'].apply(np.floor)
但是,出现以下错误:
TypeError unsupported operand type(s) for -: 'datetime.datetime' and 'float'
我看到CreateDate / EndDate是dtype:datetime64 [ns]
答案 0 :(得分:1)
问题出在那
df['diff_months'] = now - df['MaxDate']
找到最大值后,新创建的列的类型将更改,因此您可以通过简单地使用pd.to_datetime
df['diff_months'] = now - pd.to_datetime(df['MaxDate'])
我尝试了一个小例子,结果如下:
In [36]: new_df['temp_date'] = new_df[['date','new_date']].max(axis=1)
In [37]: now = datetime.now()
In [38]: new_df['diff_mon'] = now-new_df['temp_date']
TypeError: unsupported operand type(s) for -: 'datetime.datetime' and 'str'
但是,将其转换为日期时间
In [39]: new_df['diff_mon'] = now-pd.to_datetime(new_df['temp_date'])
In [40]: new_df['diff_mon']
Out[40]:
0 7487 days 19:20:37.060114
1 7547 days 19:20:37.060114