Replace space with comma in loop

Question

How I can convert csv data that contain space into comma?

My code

import csv
from pprint import pprint

with open('flare.csv', 'rb') as f:
    reader = str(csv.reader(f))

    for row in reader.splitlines():
        print row

Data

value,id
1 aah
1 aan
3 acc
4 account
1 accounts
1 action
6 ada
3 ade
1 adik
2 admin

Target output

value,id
1,aah
1,aan
3,acc
4,account
1,accounts
1,action
6,ada
3,ade
1,adik
2,admin

It contains just the one space? How about `str.replace(' ', ',')`? — President James K. Polk, Jun 15 '17 at 19:51
[Duplicate](https://stackoverflow.com/questions/19759423/convert-a-space-delimited-file-to-comma-separated-values-file-in-python)? — Yonlif, Jun 15 '17 at 19:54
What do you think `reader = str(csv.reader(f))` is doing? Because I doubt it's doing anything you would consider useful. — juanpa.arrivillaga, Jun 15 '17 at 19:58
Ok sorry, But if you would have tried to read a bit about strings before, you could have save this question from us. I don't think this question is helping to SO so its need to be deleted. — Yonlif, Jun 15 '17 at 20:04

score 3 · Accepted Answer · answered Jun 15 '17 at 19:56

3

Use csv to write your columns as well, just change the delimiter:

import csv

with open('flare.csv', 'rb') as f_in, open("out_flare.csv", "wb") as f_out:
    reader = csv.reader(f_in, delimiter=" ")
    writer = csv.writer(f_out, delimiter=",")
    writer.writerows(reader)

This will make it safe compared to blindly replacing characters as in certain situations your CSV entries will need quotes added around them.

answered Jun 15 '17 at 19:56

zwer

24,943
3
48
66

ooops! you are right; apart from naming my answer is exactly the same as yours and mine came in later... sorry! (i assume you were joking about the carbon-copy..) +1 – hiro protagonist Jun 15 '17 at 20:07
@hiroprotagonist - 'twas a joke ;) ... btw. to add something useful, one should always use binary modes when reading/writing CSVs so that the underlying OS doesn't disturb the new lines. That was the only difference between our answers :) – zwer Jun 15 '17 at 20:09

John · Answer 2 · 2017-06-15T20:06:57.693

2

You can specify delimiter=' ' to the reader function.

reader = csv.reader(f, delimiter=' ')

It is described here https://docs.python.org/2/library/csv.html#csv-fmt-params

edited Jun 15 '17 at 20:06

answered Jun 15 '17 at 19:52

John

21
4

2

... why `str(csv.reader(f))`... that won't return anything useful. – juanpa.arrivillaga Jun 15 '17 at 19:56
Sorry somehow my edit got save wrong, and I copied, saved and then put the sugested parameter in there, but it did not show up. thanks for reminding. – John Jun 15 '17 at 20:01

score 0 · Answer 3 · answered Jun 15 '17 at 19:53

Going one line at a time here what you would want to do is:

line = line.split(" ")
line = line.join(",")

Then print back out this line and it should solve your issue. The first part splits apart the line by spaces into a list and the second part then joins the pieces of the list back together into a string with your desired comma.

Replace space with comma in loop

3 Answers3