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[] and {} vs list() and dict(), which is better?
I understand that they are both essentially the same thing, but in terms of style, which is the better (more Pythonic) one to use to create an empty list or dict?
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Purpose of Unions in C and C++
...ed unions earlier comfortably; today I was alarmed when I read this post and came to know that this code
15 Answers
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How should I ethically approach user password storage for later plaintext retrieval?
As I continue to build more and more websites and web applications I am often asked to store user's passwords in a way that they can be retrieved if/when the user has an issue (either to email a forgotten password link, walk them through over the phone, etc.) When I can I fight bitterly against thi...
List comprehension vs map
...re NOT making a lambda for the purpose, but using the same function in map and a listcomp). List comprehensions may be faster in other cases and most (not all) pythonistas consider them more direct and clearer.
An example of the tiny speed advantage of map when using exactly the same function:
$ p...
NumPy: function for simultaneous max() and min()
numpy.amax() will find the max value in an array, and numpy.amin() does the same for the min value. If I want to find both max and min, I have to call both functions, which requires passing over the (very big) array twice, which seems slow.
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What is the difference between “int” and “uint” / “long” and “ulong”?
I know about int and long (32-bit and 64-bit numbers), but what are uint and ulong ?
5 Answers
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Difference between BeautifulSoup and Scrapy crawler?
I want to make a website that shows the comparison between amazon and e-bay product price.
Which of these will work better and why? I am somewhat familiar with BeautifulSoup but not so much with Scrapy crawler .
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How do I change permissions for a folder and all of its subfolders and files in one step in Linux?
I would like to change permissions of a folder and all its sub folders and files in one step (command) in Linux.
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What is the best way to solve an Objective-C namespace collision?
...uld prefix them with "IBM"; if you work for Microsoft, you could use "MS"; and so on. Sometimes the initials refer to the project, e.g. Adium prefixes classes with "AI" (as there is no company behind it of that you could take the initials). Apple prefixes classes with NS and says this prefix is rese...
Is Java “pass-by-reference” or “pass-by-value”?
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Java is always pass-by-value.
Unfortunately, we never handle an object at all, instead juggling object-handles called references (which are passed by value of course). The chosen terminology and semantics easily confuse many beginners.
It goes like this:
public static void main(...