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Converting a list to a set changes element order
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113
A set is an unordered data structure, so it does not preserve the insertion order.
This depends...
Passing an array to a function with variable number of args in Swift
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answered Jun 3 '14 at 20:53
manojldsmanojlds
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How does PHP 'foreach' actually work?
...ction iterate($arr) {
foreach ($arr as $v) {}
}
$outerArr = [0, 1, 2, 3, 4];
iterate($outerArr);
Here, $arr will be duplicated to prevent IAP changes on $arr from leaking to $outerArr. In terms of the conditions above, the array is not a reference (is_ref=0) and is used in two places (refcoun...
What does the “at” (@) symbol do in Python?
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331
An @ symbol at the beginning of a line is used for class, function and method decorators.
Rea...
Test if lists share any items in python
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322
Short answer: use not set(a).isdisjoint(b), it's generally the fastest.
There are four common...
Looping over a list in Python
...with sublists in it. I want to print all the sublists with length equal to 3.
4 Answers
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How to swap keys and values in a hash
... (in essence, by letting you access keys through values):
{a: 1, b: 2, c: 3}.key(1)
=> :a
If you want to keep the inverted hash, then Hash#invert should work for most situations:
{a: 1, b: 2, c: 3}.invert
=> {1=>:a, 2=>:b, 3=>:c}
BUT...
If you have duplicate values, invert will...
Bootstrap 3 breakpoints and media queries
On the Bootstrap 3 media queries documentation it says:
10 Answers
10
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What is the equivalent of MATLAB's repmat in NumPy
...h multiple dimensions and gives a similar result to matlab. (Numpy gives a 3d output array as you would expect - matlab for some reason gives 2d output - but the content is the same).
Matlab:
>> repmat([1;1],[1,1,1])
ans =
1
1
Python:
In [46]: a = np.array([[1],[1]])
In [47]: n...