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What does “S3 methods” mean in R?
Since I am fairly new to R, I do not know what the S3 methods and objects are. I found that there are S3 and S4 object systems, and some recommend to use S3 over S4 if possible (See Google's R Style Guide at http://google-styleguide.googlecode.com/svn/trunk/google-r-style.html )*. However, I do not...
What is the 'dynamic' type in C# 4.0 used for?
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The dynamic keyword is new to C# 4.0, and is used to tell the compiler that a variable's type can change or that it is not known until runtime. Think of it as being able to interact with an Object without having to cast it.
dynamic cust = GetCustomer();
cust.Fir...
How should equals and hashcode be implemented when using JPA and Hibernate
How should model class's equals and hashcode be implemented in Hibernate? What are the common pitfalls? Is the default implementation good enough for most cases? Is there any sense to use business keys?
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What is the difference between DAO and Repository patterns?
What is the difference between Data Access Objects (DAO) and Repository patterns? I am developing an application using Enterprise Java Beans (EJB3), Hibernate ORM as infrastructure, and Domain-Driven Design (DDD) and Test-Driven Development (TDD) as design techniques.
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StringIO in Python3
I am using Python 3.2.1 and I can't import the StringIO module. I use
io.StringIO and it works, but I can't use it with numpy 's genfromtxt like this:
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How do ACID and database transactions work?
What is the relationship between ACID and database transaction?
8 Answers
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Difference between array_map, array_walk and array_filter
What exactly is the difference between array_map , array_walk and array_filter . What I could see from documentation is that you could pass a callback function to perform an action on the supplied array. But I don't seem to find any particular difference between them.
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Real differences between “java -server” and “java -client”?
Is there any real practical difference between "java -server" and "java -client"?
11 Answers
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How to record webcam and audio using webRTC and a server-based Peer connection
I would like to record the users webcam and audio and save it to a file on the server. These files would then be able to be served up to other users.
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When to use nested classes and classes nested in modules?
I'm pretty familiar with when to use subclasses and modules, but more recently I've been seeing nested classes like this:
5...