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How to use pip with Python 3.x alongside Python 2.x
I installed Python 3.x (besides Python 2.x on Ubuntu) and slowly started to pair modules I use in Python 2.x.
10 Answers
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Double not (!!) operator in PHP
... You can use as many as you want. If there is an odd number of 'bangs' (exclamation points) it will be a NOT operation same as !value, and if there is an even number of bangs it will be the same as (bool) value.
– diamondsea
Mar 22 '18 at 3:24
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Do Swift-based applications work on OS X 10.9/iOS 7 and lower?
Will Swift-based applications work on OS X 10.9 (Mavericks)/iOS 7 and lower?
19 Answers
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Reset C int array to zero : the fastest way?
...all-bits-zero is a valid representation of 0 for all integer types in all existing C and C++ implementations, which is why the committee was able to add that requirement. (There is no similar guarantee for floating-point or pointer types.)
– Keith Thompson
Jun ...
Are tuples more efficient than lists in Python?
...tuple is much faster than assigning a list.
>>> def a():
... x=[1,2,3,4,5]
... y=x[2]
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>>> def b():
... x=(1,2,3,4,5)
... y=x[2]
...
>>> import dis
>>> dis.dis(a)
2 0 LOAD_CONST 1 (1)
3 LOAD_CONST ...
Drawing a dot on HTML5 canvas [duplicate]
...rawing a line on the HTML5 canvas is quite straightforward using the context.moveTo() and context.lineTo() functions.
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What is the benefit of using $() instead of backticks in shell scripts?
...ng to figure out if some form of escaping will work on the backticks.
An example, though somewhat contrived:
deps=$(find /dir -name $(ls -1tr 201112[0-9][0-9]*.txt | tail -1l) -print)
which will give you a list of all files in the /dir directory tree which have the same name as the earliest date...
Using LINQ to remove elements from a List
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Well, it would be easier to exclude them in the first place:
authorsList = authorsList.Where(x => x.FirstName != "Bob").ToList();
However, that would just change the value of authorsList instead of removing the authors from the previous collection....
Create an empty list in python with certain size
...None, None, None, None, None, None, None, None]
Assigning a value to an existing element of the above list:
>>> l[1] = 5
>>> l
[None, 5, None, None, None, None, None, None, None, None]
Keep in mind that something like l[15] = 5 would still fail, as our list has only 10 element...
Which method performs better: .Any() vs .Count() > 0?
in the System.Linq namespace, we can now extend our IEnumerable's to have the Any() and Count() extension methods .
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