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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...
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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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 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,...
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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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 ...
Python - Create list with numbers between 2 values?
How would I create a list with values between two values I put in?
For example, the following list is generated for values from 11 to 16:
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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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What is the syntax rule for having trailing commas in tuple definitions?
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In all cases except the empty tuple the comma is the important thing. Parentheses are only required when required for other syntactic reasons: to distinguish a tuple from a set of function arguments, operator precedence, or to allow line b...