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How to remove an element from a list by index
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Use del and specify the index of the element you want to delete:
>>> a = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9]
>>> del a[-1]
>>> a
[0, 1, 2, 3, 4, 5, 6, 7, 8]
Also supports slices:
>>> del a[2:4]
>...
What is the scope of variables in JavaScript?
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TLDR
JavaScript has lexical (also called static) scoping and closures. This means you can tell the scope of an identifier by looking at the source code.
The four scopes are:
Global - visible by everything
Function - visible within a function (and its sub-functions and blocks)
Bloc...
How to shorten my conditional statements
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Put your values into an array, and check if your item is in the array:
if ([1, 2, 3, 4].includes(test.type)) {
// Do something
}
If a browser you support doesn't have the Array#includes method, you can use this polyfill.
Short explanation of the ...
Install dependencies globally and locally using package.json
...d to do this. What you probably want to do is just put those types of command dependencies for build/test etc. in the devDependencies section of your package.json. Anytime you use something from scripts in package.json your devDependencies commands (in node_modules/.bin) act as if they are in your...
How to check if a number is a power of 2
...eturn (x != 0) && ((x & (x - 1)) == 0);
}
Explanation
First and foremost the bitwise binary & operator from MSDN definition:
Binary & operators are predefined for the integral types and bool. For
integral types, & computes the logical bitwise AND of its operands.
F...
What is the difference between tree depth and height?
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The difference between them is that in one case you count number of nodes and in other number of edges on the shortest path between root and concrete node.
Which is which?
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I want to remove double quotes from a String
...s).
Here's how it works:
['"] is a character class, matches both single and double quotes. you can replace this with " to only match double quotes.
+: one or more quotes, chars, as defined by the preceding char-class (optional)
g: the global flag. This tells JS to apply the regex to the entire st...
Using jQuery to compare two arrays of Javascript objects
...that I'd like to compare to see if they are the same. The objects may not (and most likely will not) be in the same order in each array. Each array shouldn't have any more than 10 objects. I thought jQuery might have an elegant solution to this problem, but I wasn't able to find much online.
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What is the equivalent of MATLAB's repmat in NumPy
... repmat(a, m, n) is tile(a, (m, n)).
This works with 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
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Why is January month 0 in Java Calendar?
...a date/time API. Listing what's wrong with it would take a very long time (and I'm sure I don't know half of the problems). Admittedly working with dates and times is tricky, but aaargh anyway.
Do yourself a favour and use Joda Time instead, or possibly JSR-310.
EDIT: As for the reasons why - as n...
