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How to convert a negative number to positive?
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216
>>> n = -42
>>> -n # if you know n is negative
42
>>> abs(n) ...
Iterating over every two elements in a list
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21 Answers
21
Active
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How to merge lists into a list of tuples?
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In Python 2:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]
>>> zip(list_a, list_b)
[(1, 5), (2, 6), (3, 7), (4, 8)]
In Python 3:
>>> list_a = [1, 2, 3, 4]
>>> list_b = [5, 6, 7, 8]...
What does the tilde (~) mean in my composer.json file?
...de means next significant release. In your case, it is equivalent to >= 2.0, < 3.0.
The full explanation is at Tilde Version Range docs page:
The ~ operator is best explained by example: ~1.2 is equivalent to >=1.2 <2.0.0, while ~1.2.3 is equivalent to >=1.2.3 <1.3.0.
Ano...
How to use php serialize() and unserialize()
.... But how do you pass this array to Javascript?
Array ( [1] => elem 1 [2] => elem 2 [3] => elem 3 )
The answer is serialization. In case of PHP/Javascript, JSON is actually the better serialization format:
{ 1 : 'elem 1', 2 : 'elem 2', 3 : 'elem 3' }
Javascript can easily reverse thi...
What does Bump Version stand for?
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271
It means to increment the version number to a new, unique value.
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What are the GCC default include directories?
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answered Jul 12 '11 at 15:01
Ihor KaharlichenkoIhor Kaharlichenko
4,80611 gold badge2323 silver badges2929 bronze badges
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bool operator ++ and --
... the integral value is anything else - notably this includes 0 [false] and 2 or more [true]).
So as a short-hand ++ worked, and -- didn't.
++ is allowed on bools for compatibility with this, but its use is deprecated in the standard and it was removed in C++17.
This assumes that I only use x as an ...
How do I check the difference, in seconds, between two dates?
...ates, use total_seconds like this:
import datetime as dt
a = dt.datetime(2013,12,30,23,59,59)
b = dt.datetime(2013,12,31,23,59,59)
(b-a).total_seconds()
86400.0
#note that seconds doesn't give you what you want:
(b-a).seconds
0
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Cast Object to Generic Type for returning
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212
You have to use a Class instance because of the generic type erasure during compilation.
publ...