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@glauesppen
Forked from kelvintaywl/split.py
Created January 22, 2020 18:37
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Python Script to split CSV files into smaller files based on number of lines
import csv
import sys
import os
# example usage: python split.py example.csv 200
# above command would split the `example.csv` into smaller CSV files of 200 rows each (with header included)
# if example.csv has 401 rows for instance, this creates 3 files in same directory:
# - `example_1.csv` (row 1 - 200)
# - `example_2.csv` (row 201 - 400)
# - `example_3.csv` (row 401)
CURRENT_DIR = os.path.dirname(os.path.realpath(__file__))
filename = sys.argv[1]
full_file_path = os.path.join(CURRENT_DIR, filename)
file_name = os.path.splitext(full_file_path)[0]
rows_per_csv = int(sys.argv[2]) if len(sys.argv) > 2 else 5000
with open(filename) as infile:
reader = csv.DictReader(infile)
header = reader.fieldnames
rows = [row for row in reader]
pages = []
row_count = len(rows)
start_index = 0
# here, we slice the total rows into pages, each page having [row_per_csv] rows
while start_index < row_count:
pages.append(rows[start_index: start_index+rows_per_csv])
start_index += rows_per_csv
for i, page in enumerate(pages):
with open('{}_{}.csv'.format(file_name, i+1), 'w+') as outfile:
writer = csv.DictWriter(outfile, fieldnames=header)
writer.writeheader()
for row in page:
writer.writerow(row)
print('DONE splitting {} into {} files'.format(filename, len(pages)))
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