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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...
Wolfram's Rule 34 in XKCD [closed]
The hover "joke" in #505 xkcd touts "I call rule 34 on Wolfram's Rule 34".
12 Answers
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How to include PHP files that require an absolute path?
... just a question, why realpath() for $_SERVER["DOCUMENT_ROOT"]? This shall not output always the canonical path?
– João Pimentel Ferreira
Nov 15 '15 at 0:30
add a comment...
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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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...
Is there a built-in function to print all the current properties and values of an object?
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You are really mixing together two different things.
Use dir(), vars() or the inspect module to get what you are interested in (I use __builtins__ as an example; you can use any object instead).
>>> l = dir(__builtins__)
>...
When to use setAttribute vs .attribute= in JavaScript?
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This answer is not clear enough...I don't really feel I understand this yet.
– temporary_user_name
Oct 24 '13 at 21:48
1
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Why is __init__() always called after __new__()?
... new instance.
__new__ is the first step of instance creation. It's called first, and is
responsible for returning a new
instance of your class.
In contrast,
__init__ doesn't return anything; it's only responsible for initializing the
instance after it's been created.
In ge...