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Why is arr = [] faster than arr = new Array?
...BER, IDENTIFIER)
new Array: NEW, IDENTIFIER
new Array(): NEW, IDENTIFIER, CALL
new Array(5): NEW, IDENTIFIER, CALL (NUMBER)
new Array(5,4): NEW, IDENTIFIER, CALL (NUMBER, NUMBER)
new Array(5, foo): NEW, IDENTIFIER, CALL (NUMBER, IDENTIFIER)
Hopefully this should provide you a sufficient visualizat...
Difference between a theta join, equijoin and natural join
...
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...
How to send a “multipart/form-data” with requests in python?
...
Basically, if you specify a files parameter (a dictionary), then requests will send a multipart/form-data POST instead of a application/x-www-form-urlencoded POST. You are not limited to using actual files in that dictionary, howe...
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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Convert Enumeration to a Set/List
...; vt = new Vector<String>();
vt.add("java");
vt.add("php");
vt.add("array");
vt.add("string");
vt.add("c");
Enumeration<String> enm = vt.elements();
List<String> ll = Collections.list(enm);
System.out.println("List el...