读取csv文件中的特定行,python

Question

在CSV使用python 的文件中,我们可以逐行或逐行读取所有文件,我想读取特定行(行号24示例)而不读取所有文件和所有行.

Answer 1

你可以使用linecache.getline:

linecache.getline(filename,lineno [,module_globals])

从名为filename的文件中获取line lineno.此函数永远不会引发异常 - 它将在错误时返回''(终止的换行符将包含在找到的行中).

import linecache


line = linecache.getline("foo.csv",24)

或者使用itertools中的消耗配方来移动指针:

import collections
from itertools import islice

def consume(iterator, n):
    "Advance the iterator n-steps ahead. If n is none, consume entirely."
    # Use functions that consume iterators at C speed.
    if n is None:
        # feed the entire iterator into a zero-length deque
        collections.deque(iterator, maxlen=0)
    else:
        # advance to the empty slice starting at position n
        next(islice(iterator, n, n), None)

with open("foo.csv") as f:
    consume(f,23)
    line = next(f)