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What is the difference between RDF and OWL? [closed]
I am trying to grasp the concept of Semantic Web. I am finding it hard to understand what exactly is the difference between RDF and OWL. Is OWL an extension of RDF or these two are totally different technologies?
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namespaces for enum types - best practices
...e 'larger' enum element names. Still, the namespace solution has two possible implementations: a dummy class with nested enum, or a full blown namespace.
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Pandas aggregate count distinct
...user activity and I want to generate a report of total duration and the number of unique users per day.
3 Answers
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Import package.* vs import package.SpecificType [duplicate]
... specific type (i.e. import java.lang.ClassLoader )? Would the second one be a more advisable way to use than the other one?
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Best way to test SQL queries [closed]
I have run into a problem wherein we keep having complex SQL queries go out with errors. Essentially this results in sending mail to the incorrect customers and other 'problems' like that.
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Which is faster : if (bool) or if(int)?
The above topic made me do some experiments with bool and int in if condition. So just out of curiosity I wrote this program:
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Simplest/Cleanest way to implement singleton in JavaScript?
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I think the easiest way is to declare a simple object literal:
var myInstance = {
method1: function () {
// ...
},
method2: function () {
// ...
}
};
If you want private members on your singleton instance, you can do something like this:
var myInstance ...
Vagrant error: NFS is reporting that your exports file is invalid
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Try using the known good versions of VirtualBox and Vagrant noted in Discourse as Your First Rails App:
Vagrant 1.1.2
VirtualBox 4.2.10
I was having the same issue on Mac (OS X 10.9 (Mavericks)), but rolling back to these versions seemed to fix it for me.
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What are Aggregates and PODs and how/why are they special?
This FAQ is about Aggregates and PODs and covers the following material:
6 Answers
6...
Take the content of a list and append it to another list
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You probably want
list2.extend(list1)
instead of
list2.append(list1)
Here's the difference:
>>> a = range(5)
>>> b = range(3)
>>> c = range(2)
>>> b.append(a)
>>> b
[0, 1, 2, [0, 1...