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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
... gcc-4.8 1.53s 1.52s -Os
In some cases you can alleviate the effect of disadvantageous optimizations by asking gcc to optimize for your particular processor (using options -mtune=native or -march=native):
Processor Compiler Time (-O2 -mtune=native) Time (-Os...
How to find list of possible words from a letter matrix [Boggle Solver]
Lately I have been playing a game on my iPhone called Scramble. Some of you may know this game as Boggle. Essentially, when the game starts you get a matrix of letters like so:
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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__)
>...
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...
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...
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...
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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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...
Django: Get list of model fields?
...s which (ultimately) inherits from models.Model . I want to get a list of all the fields defined for this model. For example, phone_number = CharField(max_length=20) . Basically, I want to retrieve anything that inherits from the Field class.
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javascript: Clear all timeouts?
Is there a way to clear all time outs from a given window? I suppose the timeouts are stored somewhere in the window object but couldn't confirm that.
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