Creating a list using csv.reader()

Question

I'm trying to create a list in python from a csv file. The CSV file contains only one column, with about 300 rows of data. The list should (ideally) contain a string of the data in each row.

When I execute the below code, I end up with a list of lists (each element is a list, not a string). Is the CSV file I'm using formatted incorrectly, or is there something else I'm missing?

filelist = []                
with open(r'D:\blah\blahblah.csv', 'r') as expenses:
    reader = csv.reader(expenses)
    for row in reader:
        filelist.append(row)

A CSV is a sequence of rows. A row is a sequence of column values. The column values are strings. So, iterating a CSV like this should give you a list of lists of strings. — abarnert
– abarnert, Commented May 13, 2013 at 22:38

Blender · Accepted Answer · 2013-05-13 22:20:56Z

7

row is a row with one field. You need to get the first item in that row:

filelist.append(row[0])

Or more concisely:

filelist = [row[0] for row in csv.reader(expenses)]

answered May 13, 2013 at 22:20

Blender

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1 Comment

Schack Over a year ago

Thank you, this seems to work. It didn't occur to me to stress the specific item within the row, when there is only one item to begin with.

juwens · Accepted Answer · 2013-05-13 22:26:42Z

1

It seems your "csv" doesn't contain any seperator like ";" or ",". Because you said it only contains 1 column. So it ain't a real csv and there shouldn't be a seperator.

so you could simply read the file line-wise:

filelist = []
for line in open(r'D:\blah\blahblah.csv', 'r').readlines():
    filelist.append(line.strip())

answered May 13, 2013 at 22:26

juwens

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2 Comments

Robsdedude Over a year ago

Not a good idea because of escaped separators and quotes and other csv typical signs...

juwens Over a year ago

Yes COULD be. Depends on the input file and if it is a rfc-compliant csv or just plain text file.

Robsdedude · Accepted Answer · 2013-05-13 22:22:34Z

0

Each row is read as list of cells. So what you want to do is

output = [ row[0] for row in reader ]

since you only have the first cell filled out in each row.

answered May 13, 2013 at 22:22

Robsdedude

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1 Comment

Robsdedude Over a year ago

So slow when typing on my cellphone -.-*

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