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What is the difference between '/' and '//' when used for division?

...floating point division, and the latter is floor division, sometimes also called integer division. In Python 2.2 or later in the 2.x line, there is no difference for integers unless you perform a from __future__ import division, which causes Python 2.x to adopt the 3.x behavior. Regardless of the ...
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How to get line count of a large file cheaply in Python?

... You can't get any better than that. After all, any solution will have to read the entire file, figure out how many \n you have, and return that result. Do you have a better way of doing that without reading the entire file? Not sure... The best solution will always ...
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How to avoid isset() and empty()

... For those interested, I have expanded this topic into a small article, which provides the below information in a somewhat better structured form: The Definitive Guide To PHP's isset And empty IMHO you should think about not just making the app "E_NOTICE compatible", but restructu...
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How to get current route in Symfony 2?

... not a route. As such, Symfony doesn't know what route that is for. Typically, you have one route to one controller, so it may seem weird that this can't report anything besides "_internal", however, it is possible to create general-purpose controllers that get associated with more than one route ...
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How to measure time in milliseconds using ANSI C?

... Doesn't this measure cpu time and not wall time? – krs013 Feb 1 '15 at 4:53  |  show 1 more comment ...
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Creating a singleton in Python

...mple implementation: class Singleton(type): _instances = {} def __call__(cls, *args, **kwargs): if cls not in cls._instances: cls._instances[cls] = super(Singleton, cls).__call__(*args, **kwargs) return cls._instances[cls] class Logger(object): __meta...
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HTML5 Email Validation

...e="Submit"> </form> And when the user press submit, it automatically shows an error message like: share | improve this answer | follow | ...
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Why doesn't Python have a sign function?

... it wasn't accepted, because they didn't agree on what it should return in all the edge cases (+/-0, +/-nan, etc) So they decided to implement only copysign, which (although more verbose) can be used to delegate to the end user the desired behavior for edge cases - which sometimes might require the...
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Regular expression for letters, numbers and - _

... To actually cover your pattern, i.e, valid file names according to your rules, I think that you need a little more. Note this doesn't match legal file names from a system perspective. That would be system dependent and more libera...
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How to add an extra column to a NumPy array

...for a way to add a bias unit to my artificial neuronal network in batch on all layers at once, and this is the perfect answer. – gaborous Aug 18 '16 at 15:07 ...