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What is a None value?
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Martijn's answer explains what None is in Python, and correctly states that the book is misleading. Since Python programmers as a rule would never say
Assigning a value of None to a variable is one way to reset it to
its original, empty...
Checking if a double (or float) is NaN in C++
...tation for your compiler, of course...
– dmckee --- ex-moderator kitten
Feb 20 '09 at 19:21
39
-1...
Are 2^n and n*2^n in the same time complexity?
Resources I've found on time complexity are unclear about when it is okay to ignore terms in a time complexity equation, specifically with non-polynomial examples.
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Why does C++11 not support designated initializer lists as C99? [closed]
...ructors. If it makes sense to initialize just one member then that can be expressed in the program by implementing an appropriate constructor. This is the sort of abstraction C++ promotes.
On the other hand the designated initializers feature is more about exposing and making members easy to access...
How can I access and process nested objects, arrays or JSON?
I have a nested data structure containing objects and arrays. How can I extract the information, i.e. access a specific or multiple values (or keys)?
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How to convert string representation of list to a list?
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>>> import ast
>>> x = u'[ "A","B","C" , " D"]'
>>> x = ast.literal_eval(x)
>>> x
['A', 'B', 'C', ' D']
>>> x = [n.strip() for n in x]
>>> x
['A', 'B', 'C', 'D']
ast.literal_eval:
With ast.literal_eval,...
Ternary operator is twice as slow as an if-else block?
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To answer this question, we'll examine the assembly code produced by the X86 and X64 JITs for each of these cases.
X86, if/then
32: foreach (int i in array)
0000007c 33 D2 xor edx,edx
0000007e 83 7E 04 00 ...
How to get first character of string?
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What you want is charAt.
var x = 'some string';
alert(x.charAt(0)); // alerts 's'
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How do I calculate the normal vector of a line segment?
Suppose I have a line segment going from (x1,y1) to (x2,y2). How do I calculate the normal vector perpendicular to the line?
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How can I change the color of pagination dots of UIPageControl?
... Core Graphics to render the dots in the colors you specify.
You use the exposed properties to customize and control it.
If you want to you can register a delegate object to get notifications when the user taps on one of the little page dots. If no delegate is registered then the view will not rea...