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python pandas dataframe to dictionary

...ame, and intend to convert it to python dictionary - the first column will be the key and the second will be the value. Thank you in advance. ...
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Simple explanation of MapReduce?

Related to my CouchDB question. 8 Answers 8 ...
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Ruby: Easiest Way to Filter Hash Keys?

...dated. I'm adding an update here to help others avoid getting sidetracked by this answer like I did. As the other answer mentions, Ruby >= 2.5 added the Hash#slice method which was previously only available in Rails. Example: > { one: 1, two: 2, three: 3 }.slice(:one, :two) => {:one=&gt...
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Creating a new column based on if-elif-else condition

... To formalize some of the approaches laid out above: Create a function that operates on the rows of your dataframe like so: def f(row): if row['A'] == row['B']: val = 0 elif row['A'] > row['B']: val = 1 else: val = -1 return va...
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What characters can be used for up/down triangle (arrow without stem) for display in HTML?

... Unicode arrows heads: ▲ - U+25B2 BLACK UP-POINTING TRIANGLE ▼ - U+25BC BLACK DOWN-POINTING TRIANGLE ▴ - U+25B4 SMALL BLACK UP-POINTING TRIANGLE ▾ - U+25BE SMALL BLACK DOWN-POINTING TRIANGLE For ▲ and ▼ use ▲ and ▼ respect...
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How to list active / open connections in Oracle?

Is there any hidden table, system variable or something to show active connections in a given moment? 9 Answers ...
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What is the difference between class and instance attributes?

Is there any meaningful distinction between: 5 Answers 5 ...
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Reshape three column data frame to matrix (“long” to “wide” format) [duplicate]

... There are many ways to do this. This answer starts with what is quickly becoming the standard method, but also includes older methods and various other methods from answers to similar questions scattered around this site. tmp <- data.frame(x=gl(2,3, labels=letters[24:25]), y...
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PHP abstract properties

Is there any way to define abstract class properties in PHP? 9 Answers 9 ...
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简单谈谈软件配置管理 - 项目管理 - 清泛网 - 专注C/C++及内核技术

...置项,建立和维护配置库;配置库管理;执行配置审计 b)配置控制委员会(CCB):批准基线库的生成;评估和审核变更请求,并确保批准的更改得到实施. c)QA:配置管理活动审查 2、配置管理的资源 a)配置库的服务器 b)...