Inconsistent output for csv writer in python

Question

I am trying to write data in csv format to a file. The data I am writing is pairs of integers. The inconsistency is that when the number 10 is written, I get a comma between the "1" and the "0". This just happens for the number 10, not for 11 etc.

Code:

clocktimes = [0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23]

with open('testfile.csv', 'w') as tf:
    writer = csv.writer(tf)
    for hour in clocktimes:
        if hour in hourtimes:
            writer.writerow( str((hour)).split(',') + str((hourtimes[hour])).split(',') )
        else:
            writer.writerow( (str(hour)) + (str(0)) )

(hourtimes is a dictionary consisting of integers as keys and values)

Output file:
7,0
8,0
9,0
1,0,0
11,144
12,112
13,80

Does anyone know why this is happening and what I can do to prevent this outcome?

You are passing a single string to writerow. The row in writerow(row) is supposed to be a sequence of strings or numbers, according to the documentation. Your line writer.writerow( (str(hour)) + (str(0)) ) is treating the string as a list of characters, and writing them one by one to your CSV. Either don't use writerow, or pass it the correct data. — Random Davis
– Random Davis, Commented Apr 5, 2017 at 17:17
I clearly state that the hourtimes variable is a dictionary consisting of integers as keys and values. — geirmash
– geirmash, Commented Apr 5, 2017 at 18:02

Community · Accepted Answer · 2017-05-23 12:32:20Z

1

Thank you Random Davis!
I READ THE DOCUMENTATION and experimented some further and came up with this solution:

for hour in clocktimes:
        if hour in hourtimes:
            data = [hour, hourtimes[hour]]
            writer.writerow(data)
        else:
            data = [hour, 0]
            writer.writerow(data)

The data to be written is added to an array which is accepted by the writerow() method. Output is now as I wanted which is:
...
7,0
8,0
9,0
10,0
11,144
12,112
13,80
...

edited May 23, 2017 at 12:32

CommunityBot

11 silver badge

answered Apr 5, 2017 at 20:05

geirmash

1361 gold badge1 silver badge13 bronze badges

Sign up to request clarification or add additional context in comments.

Collectives™ on Stack Overflow

Inconsistent output for csv writer in python

1 Answer 1

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

Comments

Your Answer

Sign up or log in

Post as a guest

Related