在python中将一个csv拆分为多个文件

Question

我在python中有一个约5000行的csv文件，我想将其拆分为五个文件。

我为此写了一个代码，但是没有用

import codecs
import csv
NO_OF_LINES_PER_FILE = 1000
def again(count_file_header,count):
    f3 = open('write_'+count_file_header+'.csv', 'at')
    with open('import_1458922827.csv', 'rb') as csvfile:
        candidate_info_reader = csv.reader(csvfile, delimiter=',', quoting=csv.QUOTE_ALL)
        co = 0      
        for row in candidate_info_reader:
            co = co + 1
            count  = count + 1
            if count <= count:
                pass
            elif count >= NO_OF_LINES_PER_FILE:
                count_file_header = count + NO_OF_LINES_PER_FILE
                again(count_file_header,count)
            else:
                writer = csv.writer(f3,delimiter = ',', lineterminator='\n',quoting=csv.QUOTE_ALL)
                writer.writerow(row)

def read_write():
    f3 = open('write_'+NO_OF_LINES_PER_FILE+'.csv', 'at')
    with open('import_1458922827.csv', 'rb') as csvfile:


        candidate_info_reader = csv.reader(csvfile, delimiter=',', quoting=csv.QUOTE_ALL)

        count = 0       
        for row in candidate_info_reader:
            count  = count + 1
            if count >= NO_OF_LINES_PER_FILE:
                count_file_header = count + NO_OF_LINES_PER_FILE
                again(count_file_header,count)
            else:
                writer = csv.writer(f3,delimiter = ',', lineterminator='\n',quoting=csv.QUOTE_ALL)
                writer.writerow(row)

read_write()

上面的代码创建了许多内容为空的文件。

如何将一个文件分成五个csv文件？

Answer 1

我建议你不要发明轮子。有现有的解决方案。来源在这里

import os


def split(filehandler, delimiter=',', row_limit=1000,
          output_name_template='output_%s.csv', output_path='.', keep_headers=True):
    import csv
    reader = csv.reader(filehandler, delimiter=delimiter)
    current_piece = 1
    current_out_path = os.path.join(
        output_path,
        output_name_template % current_piece
    )
    current_out_writer = csv.writer(open(current_out_path, 'w'), delimiter=delimiter)
    current_limit = row_limit
    if keep_headers:
        headers = reader.next()
        current_out_writer.writerow(headers)
    for i, row in enumerate(reader):
        if i + 1 > current_limit:
            current_piece += 1
            current_limit = row_limit * current_piece
            current_out_path = os.path.join(
                output_path,
                output_name_template % current_piece
            )
            current_out_writer = csv.writer(open(current_out_path, 'w'), delimiter=delimiter)
            if keep_headers:
                current_out_writer.writerow(headers)
        current_out_writer.writerow(row)

像这样使用它：

split(open('/your/pat/input.csv', 'r'));