Series format pandas - python-3.x

Question

import pandas as pd
from datetime import datetime
import os
# get username
user = os.getlogin()
def file_process():
data = pd.read_excel('C:\\Users\\' + user + '\\My Documents\\XINVST.xls')
# Change the date and time formatting
data["INVDAT"] = data["INVDAT"].apply(lambda x: datetime.combine(x, datetime.min.time()))
data["INVDAT"] = data["INVDAT"].dt.strftime("%m-%d-%Y")
print(data)
# output to new file
# new_data = data
# new_data.to_excel('C:\\Users\\' + user + '\\Desktop\\XINVST.xls', index=None)
if __name__ == '__main__':
file_process()
I'm trying to format the INVDAT column to correct date format like 11/25/19, I've tried multiple solutions but keep running into errors like this one: TypeError: combine() argument 1 must be datetime.date, not int, I then tried to convert the integer to date type but it errors also.

Answer 1

Or you can simply use df["INVDAT"] = pd.to_datetime(df["INVDAT"], format="%m/%d/%y"), in this case you don't need the datetime pakage. For further information you should look the docs.

Answer 2

data['INVDAT'] = data['INVDAT'].astype('str')
data["INVDAT"] = pd.to_datetime(data["INVDAT"])
data["INVDAT"] = data["INVDAT"].dt.strftime("%m/%d/%Y")
This solution works but if the date representation is a single month like 12519 ( expected output 1/25/19), it fails. I tried using a conditional to add a 0 to the front if len() < 6 but it gives me an error that the dtype is int64.

Answer 3

import pandas as pd
import os
# get username
user = os.getlogin()
def file_process():
data = pd.read_excel('C:\\Users\\' + user + '\\My Documents\\XINVST.xls')
# Change the date and time formatting
data['INVDAT'] = data['INVDAT'].astype('str')
length = len(data['INVDAT'])
data['INVDAT'].pop(length - 1)
for i in data['INVDAT'].str.len():
if i <= 5:
data['INVDAT'] = data['INVDAT'].apply(lambda x: '{0:0>6}'.format(x))
length = len(data['INVDAT'])
data['INVDAT'].pop(length - 1)
data["INVDAT"] = pd.to_datetime(data["INVDAT"])
data["INVDAT"] = data["INVDAT"].dt.strftime("%m/%d/%Y")
else:
data["INVDAT"] = pd.to_datetime(data["INVDAT"])
data["INVDAT"] = data["INVDAT"].dt.strftime("%m/%d/%Y")
# output to new file
new_data = data
new_data.to_excel('C:\\Users\\' + user + '\\Desktop\\XINVST.xls', index=None)
if __name__ == '__main__':
file_process()
This is the solution, it's sloppy but works