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Where should signal handlers live in a django project?
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I actually like to make them classmethods of the model itself. That keeps everything within one class, and means you don't have to worry about importing anything.
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How to implement a binary tree?
...ice implementation. I'm just here to point out some style stuff. python usually does node is not None instead of your (node!=None). Also, you can use the __str__ function instead of the printTree method.
– Jeff Mandell
Oct 18 '15 at 2:30
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List attributes of an object
...ict__
Then you can test what type is with type() or if is a method with callable().
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Why does the C preprocessor interpret the word “linux” as the constant “1”?
Why does the C preprocessor in GCC interpret the word linux (small letters) as the constant 1 ?
5 Answers
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Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
How to make an immutable object in Python?
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Can you use namedtuple internally inside the class instead of instantiating the object externally? I'm very new to python but the advantage to your other answer is that I can have a class hide the details and also have the power of things like optional p...
Does MongoDB's $in clause guarantee order
...d index order as shown.
If you need to preserve this order, then you basically have two options.
So let's say that you were matching on the values of _id in your documents with an array that is going to be passed in to the $in as [ 4, 2, 8 ].
Approach using Aggregate
var list = [ 4, 2, 8 ];
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Map vs Object in JavaScript
...stored at a key. Because of this, Objects have been used as Maps
historically; however, there are important differences between Objects
and Maps that make using a Map better.
An Object has a prototype, so there are default keys in the map.
However, this can be bypassed using map = Object....
Should I use Vagrant or Docker for creating an isolated environment? [closed]
...I think Docker is what you want.
Vagrant is a virtual machine manager. It allows you to script the virtual machine configuration as well as the provisioning. However, it is still a virtual machine depending on VirtualBox (or others) with a huge overhead. It requires you to have a hard drive file th...
How to use Boost in Visual Studio 2010
...te's answer is pretty good already, I'm going to expand on it more specifically for Visual Studio 2010 as requested, and include information on compiling in the various optional components which requires external libraries.
If you are using headers only libraries, then all you need to do is to unar...