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How to check if a symlink exists
...urns true if the "file" exists and is a symbolic link (the linked file may or may not exist). You want -f (returns true if file exists and is a regular file) or maybe just -e (returns true if file exists regardless of type).
According to the GNU manpage, -h is identical to -L, but according to the ...
Formula to determine brightness of RGB color
I'm looking for some kind of formula or algorithm to determine the brightness of a color given the RGB values. I know it can't be as simple as adding the RGB values together and having higher sums be brighter, but I'm kind of at a loss as to where to start.
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Returning multiple values from a C++ function
Is there a preferred way to return multiple values from a C++ function? For example, imagine a function that divides two integers and returns both the quotient and the remainder. One way I commonly see is to use reference parameters:
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What is the best (idiomatic) way to check the type of a Python variable? [duplicate]
I need to know if a variable in Python is a string or a dict. Is there anything wrong with the following code?
10 Answers
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What does (x ^ 0x1) != 0 mean?
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The XOR operation (x ^ 0x1) inverts bit 0. So the expression effectively means: if bit 0 of x is 0, or any other bit of x is 1, then the expression is true.
Conversely the expression is false if x == 1.
So the test is the same a...
Should you always favor xrange() over range()?
Why or why not?
12 Answers
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What are the differences between Generics in C# and Java… and Templates in C++? [closed]
...erics are relatively new. I keep reading that Java made the wrong decision or that .NET has better implementations etc. etc.
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Does Python's time.time() return the local or UTC timestamp?
Does time.time() in the Python time module return the system's time or the time in UTC?
8 Answers
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How do I check that a number is float or integer?
How to find that a number is float or integer ?
44 Answers
44
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What is “runtime”?
...y those instructions that you did not write explicitly, but are necessary for the proper execution of your code.
Low-level languages like C have very small (if any) runtime. More complex languages like Objective-C, which allows for dynamic message passing, have a much more extensive runtime.
You a...