重新排列对象DataFrame

Question

我试图重新安排一个对象数据框架，以DDMMYYYY格式。原格式为MM/DD/YYYY。

import string
import pandas as pd
csv_file = 'export.csv'
df = pd.read_csv(csv_file, index_col=False)
df["Date1"] = df["Order_Date"].str.split(" ").str.get(0)
df["Date"] = df["Date1"].str.split("/")
zz= df["Date"]
print(zz)

>>>
0       [11, 01, 2022]
1       [11, 01, 2022]
2       [11, 01, 2022]
3       [11, 01, 2022]
4       [11, 01, 2022]
...      
2768    [11, 22, 2022]
2769    [11, 22, 2022]
2770    [11, 22, 2022]
2771    [11, 22, 2022]
2772    [11, 22, 2022]
Name: Date, Length: 2773, dtype: object

我希望输出像这样

>>>
0       [01112022]
1       [01112022]
2       [01112022]
3       [01112022]
4       [01112022]
...      

Answer 1

使用to_datetime代替将列转换为日期时间，然后使用Series.dt.strftime:

df["Date"] = pd.to_datetime(df["Order_Date"].str.split().str.get(0)).dt.strftime('%d%m%Y')

或在第一个空格前使用Series.str.extract:

df["Date"] = (pd.to_datetime(df["Order_Date"].str.extract('(.*)s+', expand=False))
.dt.strftime('%d%m%Y'))