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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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SQLite table constraint - unique on multiple columns
I can find syntax "charts" on this on the SQLite website, but no examples and my code is crashing. I have other tables with unique constraints on a single column, but I want to add a constraint to the table on two columns. This is what I have that is causing an SQLiteException with the message "syn...
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=>...
Simple explanation of MapReduce?
Related to my CouchDB question.
8 Answers
8
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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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Creating a new column based on if-elif-else condition
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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...
What characters can be used for up/down triangle (arrow without stem) for display in HTML?
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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...
What is the difference between class and instance attributes?
Is there any meaningful distinction between:
5 Answers
5
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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）...
PHP abstract properties
Is there any way to define abstract class properties in PHP?
9 Answers
9
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