ValueError: Unconverted data remains .000

Question

I'm super new to Python and just got thrown for a loop when my source csv file changed its format. The date field now has this: 2020-07-22T00:00:00.000 when what I want is this: 2020-07-22.

I need to read the source csv and append it to a database table. I looked at some other questions and found this sample code which I think will do what I want (create a copy of the csv with the newly formatted date which I can use with the rest of my code).

import csv
from datetime import datetime

with open(csvCasesVH, 'r') as source:
    with open(csvCasesVH2, 'w') as result:
        writer = csv.writer(result, lineterminator='\n')
        reader = csv.reader(source)
        source.readline()
        for row in reader:
            ts = datetime.strptime(row[0], '%Y-%m-%dT%H:%M:%S').strftime("%Y-%m-%d")
            print(ts)
            row[0]=ts
            if ts != "":
                writer.writerow(row)
source.close()
result.close()

I'm trying to figure out the datetime format - almost got there but now that this .000 hanging out there I don't know what to do with:

ValueError: unconverted data remains: .000

I would appreciate any advice. Thanks.

score 8 · Accepted Answer · answered Jul 22 '20 at 19:14

8

Try updating the line:

ts = datetime.strptime(row[0], '%Y-%m-%dT%H:%M:%S').strftime("%Y-%m-%d")

To:

ts = datetime.strptime(row[0], '%Y-%m-%dT%H:%M:%S.%f').strftime("%Y-%m-%d")

Note the .%f which is for microseconds

answered Jul 22 '20 at 19:14

Spencer Bard

1,015
6
10

score 1 · Answer 2 · answered Jul 22 '20 at 19:24

The strptime function tries to get a datetime object out of a string, to do that it needs a datetime string and it needs a format matching the string. For example lets say I have the string '25/07/2020 21:13', to extract a date I need to give it the format '%d/%m/%Y %H:%M', if I gave it the format '%d/%m/%Y %H:' it would give the error ValueError: unconverted data remains: 13 because it doesn't know what the 13 stands for (minutes?, seconds?, am/pm?). To solve this problem you can look at how the string looks like by printing it and modifying the format.

A useful site to use when working with datetime formats is https://strftime.org/.

In your case the remaining .000 probably means microseconds so you need to add it to the format: '%Y-%m-%dT%H:%M:%S.%f' (%f stands for microsecconds)

score 0 · Answer 3 · answered Mar 21 '22 at 12:05

0

Try use '%Y-%m-%dT%H:%M:%S.%f000' as the formatting string:

applying to your code:

ts = datetime.strptime(row[0], '%Y-%m-%dT%H:%M:%S.%f000').strftime("%Y-%m-%d")

answered Mar 21 '22 at 12:05

Grant Shannon

4,709
1
46
36

ValueError: Unconverted data remains .000

3 Answers3