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Cartesian product of x and y array points into single array of 2D points

... 5], [2, 5], [3, 5]]) See Using numpy to build an array of all combinations of two arrays for a general solution for computing the Cartesian product of N arrays. share | improve this...
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What is a regular expression for a MAC Address?

...at" comes from Wikipedia, not the 802.3 standards body. IEEE 802-2014 actually specifies hyphens for ordinary MAC addresses (§ 8.1 ¶ 3) and colons for the obsolescent bit-reversed notation (¶ 4). Importantly, in practice, no one observes this. We simply use one or the other, but never mix them...
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python: Change the scripts working directory to the script's own directory

... __file__ fails in "frozen" programs (created using py2exe, PyInstaller, cx_Freeze). sys.argv[0] works. @ChrisDown: If you want to follow symlinks; os.path.realpath() could be used. – jfs Apr 5 '14 at 20:12 ...
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What are “connecting characters” in Java identifiers?

... I'm not sure that actually fully answers the (implied) question of which characters may start a Java identifier. Following links we end up at Character.isJavaIdentifierStart() which states A character may start a Java identifier if and only if one...
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How does collections.defaultdict work?

... Usually, a Python dictionary throws a KeyError if you try to get an item with a key that is not currently in the dictionary. The defaultdict in contrast will simply create any items that you try to access (provided of course th...
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What is a method that can be used to increment letters?

...ded to expand it a bit beyond the scope of the original question to potentially help people who are stumbling on this from Google. I find that what I often want is something that will generate sequential, unique strings in a certain character set (such as only using letters), so I've updated this a...
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How do I access the request object or any other variable in a form's clean() method?

... but how can I access the request object? Can I modify the clean method to allow variables input? 11 Answers ...
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Collapse sequences of white space into a single character and trim string

...low, because it creates a new object for every substring and sends method calls to each of them. – Georg Schölly Jun 23 '11 at 18:55 2 ...
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Implement touch using Python?

... On Python2.7: pip install pathlib – Andre Miras Oct 24 '17 at 17:54 8 ...
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My attempt at value initialization is interpreted as a function declaration, and why doesn't A a(())

...has taught me is what is known as the "most vexing parse", which is classically demonstrated with a line such as 5 Answers ...