我所做的就是用熊猫形来称呼N行。我认为性能不是最好的，但是举个例子，如果N=1000:

import pandas as pd
yourfile = pd.read_csv('path/to/your/file.csv',nrows=1000)

我所做的就是用熊猫形来称呼N行。我认为性能不是最好的，但是举个例子，如果N=1000:

import pandas as pd
yourfile = pd.read_csv('path/to/your/file.csv',nrows=1000)

fname = input("Enter file name: ")
num_lines = 0

with open(fname, 'r') as f: #lines count
    for line in f:
        num_lines += 1

num_lines_input = int (input("Enter line numbers: "))

if num_lines_input <= num_lines:
    f = open(fname, "r")
    for x in range(num_lines_input):
        a = f.readline()
        print(a)

else:
    f = open(fname, "r")
    for x in range(num_lines_input):
        a = f.readline()
        print(a)
        print("Don't have", num_lines_input, " lines print as much as you can")


print("Total lines in the text",num_lines)

Python 3:

with open("datafile") as myfile:
    head = [next(myfile) for x in range(N)]
print(head)

Python 2:

with open("datafile") as myfile:
    head = [next(myfile) for x in xrange(N)]
print head

下面是另一种方法(Python 2和3都是):

from itertools import islice

with open("datafile") as myfile:
    head = list(islice(myfile, N))
print(head)

#!/usr/bin/python

import subprocess

p = subprocess.Popen(["tail", "-n 3", "passlist"], stdout=subprocess.PIPE)

output, err = p.communicate()

print  output

这个方法对我很有效

这对我很有效

f = open("history_export.csv", "r")
line= 5
for x in range(line):
    a = f.readline()
    print(a)