如何以最有效的内存和时间方式获取大文件的行数?
def file_len(filename):
with open(filename) as f:
for i, _ in enumerate(f):
pass
return i + 1
如何以最有效的内存和时间方式获取大文件的行数?
def file_len(filename):
with open(filename) as f:
for i, _ in enumerate(f):
pass
return i + 1
当前回答
计数= max(开放(文件))[0]
其他回答
我使用的最简单和最短的方法是:
f = open("my_file.txt", "r")
len(f.readlines())
def line_count(path):
count = 0
with open(path) as lines:
for count, l in enumerate(lines, start=1):
pass
return count
创建一个可执行脚本文件count.py:
#!/usr/bin/python
import sys
count = 0
for line in sys.stdin:
count+=1
然后将文件的内容导入python脚本:cat huge.txt | ./count.py。管道也适用于Powershell,因此您将最终计算行数。
对我来说,在Linux上它比简单的解决方案快30%:
count=1
with open('huge.txt') as f:
count+=1
您可以执行子进程并运行wc -l filename
import subprocess
def file_len(fname):
p = subprocess.Popen(['wc', '-l', fname], stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
result, err = p.communicate()
if p.returncode != 0:
raise IOError(err)
return int(result.strip().split()[0])
我发现你可以。
f = open("data.txt")
linecout = len(f.readlines())
会给你答案吗