how to convert python array(List) to CSV

Question

My csv output is not coming out the way I planned. My code:

first_row = list(ws.rows)[1]
first_row_values = []
first_row_values.append(value1)
first_row_values.append(value2)
first_row_values.append(value3)
first_row_values.extend([cell.value for cell in first_row])
print(first_row_values)
writer = csv.writer(open('output.csv', 'a+'))
writer.writerow([first_row_values])

the output in the file looks like this:

"['value1', 'value2', 'value3', 'valueA', 'valueB', 'valueC', 'valueD', 'valueE', 'valueF', 'valueG', 'valueH', 'valueI', 'valueJ']"

I'm expecting a csv output:

'value1', 'value2', 'value3', 'valueA', 'valueB', 'valueC', 'valueD', 'valueE', 'valueF', 'valueG', 'valueH', 'valueI', 'valueJ'

What am I missing here?

Remove the square brackets in writer.writerow([first_row_values]). — Mad Physicist
– Mad Physicist, Commented Apr 5, 2018 at 19:27
first_row_values is already a list, now you made it into a nested list that is the first element of your row, so the whole things gets converted to a string. — Mad Physicist
– Mad Physicist, Commented Apr 5, 2018 at 19:28

SamBG · Accepted Answer · 2018-04-05 19:40:09Z

1

As stated by Mad Physicist and Anton vBR, the set of square brackets, [], is the issue. When you put these brackets around something in python, it will create a list upon execution. So, by putting a list object, first_row_values, within square brackets, you are nesting a list within a new list, as its only element.

answered Apr 5, 2018 at 19:40

SamBG

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1 Comment

arcee123 Over a year ago

Thank you to you, Mad Physicist, and Anton vBR. All of you made something clear I didn't understand previously. Thanks again!

Kanchan Jha · Accepted Answer · 2018-04-05 20:44:35Z

1

Just removing the square brackets should give you your result.

  writer.writerow(first_row_values)

answered Apr 5, 2018 at 20:44

Kanchan Jha

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1 Comment

arcee123 Over a year ago

sorry Kanchan...I plus'd one for you, but SamBG came first.\

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