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Python

Posted by Keith Doyle
Keith Doyle
25,973 Points

Writing Python Dictionary to CSV

Just finished the regex course from Kenneth Love this morning and got a chance to put that to use this afternoon, nice timing. Had to parse a 20MB text file looking for email addresses and then write it to a CSV. Just thought I'd share what I ended up doing. Thanks for the skillz!

line = re.compile(r"\s(?P<email>[-\w\d.+]+@[-\w\d.]+)</font", re.X | re.M)


def write_dict_to_csv(csv_file, csv_columns, dict_data):
    try:
        with open(csv_file, 'w') as csvfile:
            writer = csv.DictWriter(csvfile, fieldnames=csv_columns)
            writer.writeheader()
            for key, value in dict_data.items():
                writer.writerow({'email': key, 'pifs_submitted': value})
    except IOError:
        print("I/O error", csv_file)
    return

csv_columns = ['email', 'pifs_submitted']

matches = {}

for match in line.finditer(file_data):
    if match.group('email') not in matches:
        matches[match.group('email')] = 1
    elif match.group('email') in matches:
        matches[match.group('email')] += 1
#

csv_file = 'pif_emails_counted.csv'

write_dict_to_csv(csv_file, csv_columns, matches)

1 Answer