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What is the purpose of setting a key in data.table?
I am using data.table and there are many functions which require me to set a key (e.g. X[Y] ). As such, I wish to understand what a key does in order to properly set keys in my data tables.
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SQL Server: Examples of PIVOTing String data
...SQL Server PIVOT examples. Most of the examples that I have found involve counting or summing up numbers. I just want to pivot some string data. For example, I have a query returning the following.
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IE10 renders in IE7 mode. How to force Standards mode?
On microsoft's site they claim that simple doctype declaration is enough. But even a document as short as this falls back to IE7 mode:
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Proper way to use AJAX Post in jquery to pass model from strongly typed MVC3 view
I'm a novice web programmer so please forgive me if some of my "jargon" is not correct.
I've got a project using ASP.NET using the MVC3 framework.
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Same-named attributes in attrs.xml for custom view
I'm writing a few custom views which share some same-named attributes. In their respective <declare-styleable> section in attrs.xml I'd like to use the same names for attributes:
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What's invokedynamic and how do I use it?
I keep hearing about all the new cool features that are being added to the JVM and one of those cool features is invokedynamic. I would like to know what it is and how does it make reflective programming in Java easier or better?
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What does f+++++++++ mean in rsync logs?
I'm using rsync to make a backup of my server files, and I have two questions:
4 Answers
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Java8: Why is it forbidden to define a default method for a method from java.lang.Object
Default methods are a nice new tool in our Java toolbox. However, I tried to write an interface that defines a default version of the toString method. Java tells me that this is forbidden, since methods declared in java.lang.Object may not be default ed. Why is this the case?
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What's the difference between “groups” and “captures” in .NET regular expressions?
I'm a little fuzzy on what the difference between a "group" and a "capture" are when it comes to .NET's regular expression language. Consider the following C# code:
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Most concise way to convert a Set to a List
For example, I am currently doing this:
6 Answers
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