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Difference between a theta join, equijoin and natural join
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A theta join allows for arbitrary comparison relationships (such as ≥).
An equijoin is a theta join using the equality operator.
A natural join is an equijoin on attributes that have the same name in each relationship.
Additionally,...
How to spread django unit tests over multiple files?
... you run your tests, the default behavior of the test utility is
to find all the test cases (that is, subclasses of unittest.TestCase)
in any file whose name begins with test, automatically build a test
suite out of those test cases, and run that suite.
From Django 1.6 documentation,
Tes...
Print all properties of a Python Class [duplicate]
...rint for example in order of declaration, and you do not want to do it manually, check this
– Matteo A
Aug 14 '15 at 8:41
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Header files for x86 SIMD intrinsics
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These days you should normally just include <immintrin.h>. It includes everything.
GCC and clang will stop you from using intrinsics for instructions you haven't enabled at compile time (e.g. with -march=native or -mavx2 -mbmi2 -mpopcnt -mfma ...
Dictionary vs Object - which is more efficient and why?
...ots__ = ('i', 'l')
def __init__(self, i):
self.i = i
self.l = []
all = {}
for i in range(1000000):
all[i] = Obj(i)
test_obj.py:
class Obj(object):
def __init__(self, i):
self.i = i
self.l = []
all = {}
for i in range(1000000):
all[i] = Obj(i)
test_dict.py:
all = {}
for i in...
List all the files that ever existed in a Git repository
Do you have a clean way to list all the files that ever existed in specified branch?
4 Answers
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How to set the prototype of a JavaScript object that has already been instantiated?
...n set of rules. This is currently unresolved but at least it will be officially part of JavaScript's specification.
This question is a lot more complicated than it seems on the surface, and beyond most peoples' pay grade in regards to knowledge of Javascript internals.
The prototype property of an...
Why does Python use 'magic methods'?
...lable, an object implements a method, def __len__(self) , and then it is called when you write len(obj) .
7 Answers
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A simple explanation of Naive Bayes Classification
... & part two being the confusion surrounding Training set.
In general all of Machine Learning Algorithms need to be trained for supervised learning tasks like classification, prediction etc. or for unsupervised learning tasks like clustering.
During the training step, the algorithms are taught...
python: How do I know what type of exception occurred?
I have a function called by the main program:
15 Answers
15
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