如何通过网络驱动器快速从.csv文件中获取最后一行? [英] How to quickly get the last line from a .csv file over a network drive?

问题描述

我将数千个时间序列存储在网络驱动器上的.csv文件中.在更新文件之前，我首先获取文件的最后一行以查看时间戳，然后在该时间戳之后使用数据进行更新.如何才能通过网络驱动器快速获取.csv文件的最后一行，从而不必仅使用最后一行就加载整个庞大的.csv文件?

I store thousands of time series in .csv files on a network drive. Before I update the files, I first get the last line of the file to see the timestamp and then I update with data after that timestamp. How can I quickly get the last line of a .csv file over a network drive so that I don't have to load the entire huge .csv file only to use the last line?

推荐答案

为此，有一个漂亮的reversed工具，假设您正在使用内置的csv模块:

There is a nifty reversed tool for this, assuming you are using the built-in csv module:

如何在python中的相反顺序

简而言之:

import csv
with open('some_file.csv', 'r') as f:
    for row in reversed(list(csv.reader(f))):
        print(', '.join(row))

在我的测试文件中:

1:   test, 1
2:   test, 2
3:   test, 3

这将输出:

test, 3
test, 2
test, 1

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