大文件切割Demo Python
CSV切割demo:实现了按行数切割以及按文件书切割
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time : 2021/4/2 12:17 下午
# @Author : Xinlong Chen
# @File : test.py
import math
import os
class CsvSplit:
def __mkSubFile(self, lines, dir, head, srcName, sub):
[des_filename, extname] = os.path.splitext(srcName)
filename = dir + os.sep + des_filename + '_' + str(sub) + extname
print('make file: %s' % filename)
fout = open(filename, 'w')
try:
fout.writelines([head])
fout.writelines(lines)
return sub + 1
finally:
fout.close()
def __readFromCsv(self, filename):
if os.path.exists(filename):
with open(filename, 'r') as file:
head = file.readline()
lines = file.readlines()
return head, lines, 0
else:
print("error filename")
return [], [], -1
def splitByLineCount(self, filename, dir, count: int, lines=[], head=""):
if len(lines) == 0:
head, lines, status = self.__readFromCsv(filename)
if status != 0:
return
if not os.path.exists(dir):
os.makedirs(dir)
buf = []
sub = 1
for line in lines:
buf.append(line)
if len(buf) == count:
sub = self.__mkSubFile(buf, dir, head, filename, sub)
buf = []
# judge end
if len(buf) != 0:
self.__mkSubFile(buf, dir, head, filename, sub)
def splitByFileCount(self, filename, dir, filecount=10):
head, lines, status = self.__readFromCsv(filename)
if status != 0:
return
all_length = len(lines)
each_file = math.ceil(all_length / filecount)
self.splitByLineCount(filename, dir, each_file, lines, head)
if __name__ == '__main__':
CsvSplit().splitByFileCount('weibo.csv', dir='weibo', filecount=10)
CsvSplit().splitByLineCount('weibo.csv', dir='weibo1', count=500000)
博文不定期更新,但代码可能会更新
最新代码可关注github:https://github.com/Xinlong-Chen/Split_CSV/