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Constructor of an abstract class in C#
Why is it possible to write constructor for an abstract class in C#?
As far as I know we can't instantiate an abstract class.. so what is it for?
You can't instantiate the class, right?
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Eclipse WTP vs sydeo, “ serves modules without publishing ”
I have the problem to find the performances of the plugin sysdeo by using the integrated plugin WTP of eclipse.
2 Answers
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Single huge .css file vs. multiple smaller specific .css files? [closed]
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A CSS compiler like Sass or LESS is a great way to go. That way you'll be able to deliver a single, minimised CSS file for the site (which will be far smaller and faster than a normal single CSS source file), while maintaining the nicest development ...
How to prune local tracking branches that do not exist on remote anymore
With git remote prune origin I can remove the local branches that are not on the remote any more.
31 Answers
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Can table columns with a Foreign Key be NULL?
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Yes, you can enforce the constraint only when the value is not NULL. This can be easily tested with the following example:
CREATE DATABASE t;
USE t;
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=INNOD...
How to add an extra column to a NumPy array
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I think a more straightforward solution and faster to boot is to do the following:
import numpy as np
N = 10
a = np.random.rand(N,N)
b = np.zeros((N,N+1))
b[:,:-1] = a
And timings:
In [23]: N = 10
In [24]: a = np.random.rand(N,N)
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What is the difference between setUp() and setUpClass() in Python unittest?
...erence between setUp() and setUpClass() in the Python unittest framework? Why would setup be handled in one method over the other?
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Is mongodb running?
...ps -edaf | grep mongo | grep -v grep # "ps" flags may differ on your OS
or
/etc/init.d/mongodb status # for MongoDB version < 2.6
/etc/init.d/mongod status # for MongoDB version >= 2.6
or
service mongod status
to see if mongod is running (you need to be root to do...
PHP: How to handle
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You're probably not accessing it correctly. You can output it directly or cast it as a string. (in this example, the casting is superfluous, as echo automatically does it anyway)
$content = simplexml_load_string(
'<content><![CDATA[Hello, world!...
String, StringBuffer, and StringBuilder
... a single thread then it is better to use StringBuilder. StringBuilder is more efficient than StringBuffer.
Situations:
If your string is not going to change use a String class because a String object is immutable.
If your string can change (example: lots of logic and operations in the constructi...