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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...
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...
Javascript - remove an array item by value [duplicate]
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223
You'll want to use JavaScript's Array splice method:
var tag_story = [1,3,56,6,8,90],
id_ta...
Bootstrap 3 breakpoints and media queries
On the Bootstrap 3 media queries documentation it says:
10 Answers
10
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How to Correctly Use Lists in R?
...:
Why do these two expressions not return the same result?
x = list(1, 2, 3, 4); x2 = list(1:4)
A list can contain any other class as each element. So you can have a list where the first element is a character vector, the second is a data frame, etc. In this case, you have created two different ...
HTML5 Canvas Resize (Downscale) Image High Quality?
...e. )
Here's an example of canvas scale vs my pixel perfect scale on a 1/3 scale of a zombat.
Notice that the picture might get scaled in your Browser, and is .jpegized by S.O..
Yet we see that there's much less noise especially in the grass behind the wombat, and the branches on its right. The n...