将日期列（字符串）转换为日期时间并匹配格式

Question

I'm trying to covert the next date column (str) to datetime64 and say that format doesn't match, can anyone help me pleas:)

Column:

df["Date"]

0 15/7/21... 2541 13/9/21 dtype: object

What I try:

pd.to_datetime(df["Date"], format = "%d/%m/%Y")

ValueError: time data '15/7/21' does not match format '%d/%m/%Y' (match)

I also try:

pd.to_datetime(df["Date"].astype("datetime64"), format='%d/%m/%Y')

And it convert it as datetime but there is some date the day is in the month.

Anyone know what to do?

Answer 1

%Y expects a 4-digit year. Use %y for a 2-digit year (See the docs ):

>>> import pandas as pd
>>> df = pd.DataFrame({'Date':['15/7/21','13/9/21']})
>>> df['Date']
0    15/7/21
1    13/9/21
Name: Date, dtype: object
>>> pd.to_datetime(df['Date'].astype('datetime64'),format='%d/%m/%y')
0   2021-07-15
1   2021-09-13
Name: Date, dtype: datetime64[ns]

Note that pandas is pretty good at guessing the format:

>>> pd.to_datetime(df['Date'])
0   2021-07-15
1   2021-09-13