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Best way to test for a variable's existence in PHP; isset() is clearly broken
...l scope variables as well, on can do a $defined_vars = get_defined_vars(); and then test via array_key_exists('v', $defined_vars);.
– Henrik Opel
Sep 27 '10 at 16:01
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What is the difference between visibility:hidden and display:none?
The CSS rules visibility:hidden and display:none both result in the element not being visible. Are these synonyms?
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A simple explanation of Naive Bayes Classification
I am finding it hard to understand the process of Naive Bayes, and I was wondering if someone could explain it with a simple step by step process in English. I understand it takes comparisons by times occurred as a probability, but I have no idea how the training data is related to the actual datase...
Namespace and class with the same name?
I'm organizing a library project and I have a central manager class named Scenegraph and a whole bunch of other classes that live in the Scenegraph namespace.
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Difference between null and empty (“”) Java String
What is the difference between null and the "" (empty string)?
22 Answers
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Exit single-user mode
Currently, my database is in Single User mode. When I try to expand me database, I get an error:
18 Answers
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What is the difference between a web API and a web service?
Is there any difference between a web API and a web service ? Or are they one and the same ?
12 Answers
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Difference between single and double quotes in Bash
In Bash, what are the differences between single quotes ( '' ) and double quotes ( "" )?
6 Answers
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Should flux stores, or actions (or both) touch external services?
Should the stores maintain their own state and have the ability to call network and data storage services in doing so ...in which case the actions are just dumb message passers,
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socket.io rooms or namespacing?
I am investigating nodejs/socket.io for real time chat, and I need some advice for implementing rooms.
5 Answers
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