July 2017
Intermediate to advanced
398 pages
11h 54m
Chinese
Content preview from Python数据处理
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.
103
第 6 章
数据获取与存储
找到要研究的第一个数据集，可能是向回答问题这一目标迈出的最重要一步。在第
1
章里
我们说过，你首先应该花点时间将问题细化，让问题足够具体，能够找到关于问题的好数
据，同时问题又要足够宽泛，可以让你和其他人都感兴趣。
另一种可能是，你已经找到了感兴趣的数据集，但无法提出令人信服的问题。如果你不了
解也不信任数据来源，应该花点时间调查一下。问问你自己：数据是否有效？是否更新
过？我能否信任当前以及未来的更新和出版物？
本章我们会讲到，你可以将数据保存在什么地方，以供后续使用。如果你不熟悉数据库的
话，我们也会讲到数据库的使用场景和使用方法，并演示如何创建简单数据库来存储数
据。如果你已经很熟悉数据库，或者你的数据源就是一个数据库的话，我们会讲到
Python
中基本的数据库连接结构。
如果你还没决定使用哪个数据集的话，不必担心。下面用的几个例子，你都可以在本书仓
库（
https://github.com/jackiekazil/data-wrangling
）中找到。
我们强烈建议你带着几个问题阅读本书，这样你才能更好地在实践中学习。
这些问题可能是你一直想研究的问题，也可能是与本书所探索数据相关的问
题。即使你选取的问题很简单，在编写代码中学习也是最好的学习方法。
6.1
并非所有数据生而平等
对于遇到的每一个数据集，尽管我们愿意相信其真实性和数据质量，但并非所有数据都能
符合我们的预期。即使是你目前使用的数据集，在深入研究之后也可能是无用且无效的数
据源。对于你面临的数据处理问题，在寻求自动化解决方案 ...
Become an O’Reilly member and get unlimited access to this title plus top books and audiobooks from O’Reilly and nearly 200 top publishers, thousands of courses curated by job role, 150+ live events each month,
and much more.
Read now
Unlock full access
More than 5,000 organizations count on O’Reilly
O’Reilly covers everything we've got, with content to help us build a world-class technology community, upgrade the capabilities and competencies of our teams, and improve overall team performance as well as their engagement.Julian F.
I wanted to learn C and C++, but it didn't click for me until I picked up an O'Reilly book. When I went on the O’Reilly platform, I was astonished to find all the books there, plus live events and sandboxes so you could play around with the technology.Addison B.
I’ve been on the O’Reilly platform for more than eight years. I use a couple of learning platforms, but I'm on O'Reilly more than anybody else. When you're there, you start learning. I'm never disappointed.Amir M.
I'm always learning. So when I got on to O'Reilly, I was like a kid in a candy store. There are playlists. There are answers. There's on-demand training. It's worth its weight in gold, in terms of what it allows me to do.