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Dealing with multiple Python versions and PIP?
...ple versions of Python? For example, I want to use pip to explicitly install things to either my site 2.5 installation or my site 2.6 installation.
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NumPy array initialization (fill with identical values)
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On my system (Python 2.7, Numpy 1.8), np.full() is actually slightly slower than np.empty() followed by np.fill().
– John Zwinck
Jul 25 '14 at 8:37
2
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What is the 'instanceof' operator used for in Java?
... Dog is Dog
dog instanceof Object // true - Object is the parent type of all objects
However, with Object animal = new Animal();,
animal instanceof Dog // false
because Animal is a supertype of Dog and possibly less "refined".
And,
dog instanceof Cat // does not even compile!
This is beca...
Why do we need a pure virtual destructor in C++?
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Probably the real reason that pure virtual destructors are allowed is that to prohibit them would mean adding another rule to the language and there's no need for this rule since no ill-effects can come from allowing a pure virtual destructor.
Nope, plain old virtual is enough.
If...
Keyboard shortcuts in WPF
I know about using _ instead of & , but I'm looking at all the Ctrl + type shortcuts.
10 Answers
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Logging uncaught exceptions in Python
... global type (much like using var self = this in Javascript). It doesn't really matter unless you need to access the type object inside your function, in which case you can use type_ as the argument instead.
– Ryan P
Jan 2 '13 at 17:08
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Replace whole line containing a string using Sed
...cusDowning GNU sed does not require the space; it works just fine as originally posted. If your particular sed requires the space, then by all means note which sed is incompatible and add the necessary invocation as a comment. However, please don't change working code in an accepted answer.
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Are the shift operators () arithmetic or logical in C?
...ependent for right shifts of signed values.
Wikipedia says that C/C++ 'usually' implements an arithmetic shift on signed values.
Basically you need to either test your compiler or not rely on it. My VS2008 help for the current MS C++ compiler says that their compiler does an arithmetic shift.
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C++ Tuple vs Struct
... not the purpose of this discussion so I won't dive into the detail.
We all know that writing a == or < or > operator for every single struct definition will be a painful and buggy task. Let replace our custom comparator using std::tie and rerun our benchmark.
bool operator<(const Str...
How do I import global modules in Node? I get “Error: Cannot find module ”?
I am trying to setup Node on Mac OSX Lion. It all seems to work ok, but I can't seem to import anything modules from my global modules folder. I get the error,
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