August 2022
Beginner to intermediate
463 pages
9h 22m
Chinese
Content preview from Tableau Prep即学即用
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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.
｜
331
处理自由文本
图
36
-
7
：Tweets 文章拆分、转换后所产生的十大词条
在网上很容易找到一份常用词的清单。有了这样一份清单，就可以指导你的删除工
作。图
36-8
展示了一个常用词数据集的样本。
图
36
-
8
：常用词数据集
正确设置
Join
（连接）是确保删除常用词的重要条件。首先，需要将常用词列表与
从自由文本字段中拆分出来的单词列表进行连接，然后就可以删除在两个列表中发
现的所有单词。要做到这一点，需点击连接条件的相交部分。此时连接设置应该如
图
36-9
所示。
332
｜
第
36
章
图
36
-
9
：连接设置，以删除 Tweets 文章中发现的常用词
36.3.5
将剩余的值进行分组
正如第
20
章所讨论的，
Prep Builder
的分组功能非常灵活。这最后一步是可选的，
它取决于分析师的意见。一方面，如果对不应该分组的值进行分组，你会得到不准
确的问题答案；另一方面，如果有类似的值可以分组而不分组，你将很难在“噪声”
中找到“信号”。可以对其进行调整，使得一些分组算法的敏感度更高或更低，以
更好地满足要求（见图
36-10
）。
图
36
-
10
：Group and Replace（分组和替换）功能是通过分组进行清理的一种方法
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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.