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How to reshape data from long to wide format

... +1 and you don't need to rely on external packages, since reshape comes with stats. Not to mention that it's faster! =) – aL3xa May 5 '11 at 0:07 ...
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When to use actors instead of messaging solutions such as WebSphere MQ or Tibco Rendezvous?

I've already read the question and answers to What design decisions would favour Scala's Actors instead of JMS? . 3 Answer...
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Empty set literal?

... @andy That's not an empty set - that's a set containing the number 1. You don't need the trailing comma by the way - that's only required for tuples. – sepp2k Jan 19 '15 at 13:12 ...
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Comparison of full text search engine - Lucene, Sphinx, Postgresql, MySQL?

I'm building a Django site and I am looking for a search engine. 9 Answers 9 ...
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Reverse a string in Python

...tended slice syntax. It works by doing [begin:end:step] - by leaving begin and end off and specifying a step of -1, it reverses a string. share | improve this answer | follow...
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How do servlets work? Instantiation, sessions, shared variables and multithreading

...ervlets. For information passing among those servlets I am setting session and instance variables. 8 Answers ...
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PHP Regex to check date is in YYYY-MM-DD format

...t answer? This returns true for a number of invalid dates like 2016-02-30 and 2016-09-31 – Graham Oct 11 '16 at 14:35 ...
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Why do we need Abstract factory design pattern?

...tract Factory has been accepted as the solution. To the best of my understanding, these questions represent real concerns or problems that people had, so that should get you started with some real-life examples: Is there a pattern for initializing objects created via a DI container Can't combine ...
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What is Data Transfer Object?

... A Data Transfer Object is an object that is used to encapsulate data, and send it from one subsystem of an application to another. DTOs are most commonly used by the Services layer in an N-Tier application to transfer data between itself and the UI layer. The main benefit here is that it reduc...
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Why do assignment statements return a value?

... To my understanding, assignment s = "Hello"; should only cause "Hello" to be assigned to s, but the operation shouldn’t return any value. Your understanding is 100% incorrect. Can you explain why you believe this false thing? What...