从excel中提取日期并使用python将其追加到列表中

Question

I have an column in excel which has dates in the format ''17-12-2015 19:35". How can I extract the first 2 digits as integers and append it to a list? In this case I need to extract 17 and append it to a list. Can it be done using pandas also?

Code thus far:

import pandas as pd
Location = r'F:\Analytics Materials\files\paymenttransactions.csv'
df = pd.read_csv(Location)
time = df['Creation Date'].tolist()
print (time)

Answer 1

You could extract the day of each timestamp like

from datetime import datetime
import pandas as pd

location = r'F:\Analytics Materials\files\paymenttransactions.csv'
df = pd.read_csv(location)

timestamps = df['Creation Date'].tolist()
dates = [datetime.strptime(timestamp, '%d-%m-%Y %H:%M') for timestamp in timestamps]
days = [date.strftime('%d') for date in dates]

print(days)

The '%d-%m-%Y %H:%M' and '%d' bits are format specififers, that describe how your timestamp is formatted. See eg here for a complete list of directives.

datetime.strptime parses a string into a datetime object using such a specifier. dates will thus hold a list of datetime instances instead of strings.

datetime.strftime does the opposite: It turns a datetime object into string, again using a format specifier. %d simply instructs strftime to only output the day of a date.