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What does the Ellipsis object do?
...nterpretation is purely up to whatever implements the __getitem__ function and sees Ellipsis objects there, but its main (and intended) use is in the numpy third-party library, which adds a multidimensional array type. Since there are more than one dimensions, slicing becomes more complex than just...
Finding sum of elements in Swift array
...the sum of an array of integers in swift?
I have an array called multiples and I would like to know the sum of the multiples.
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How to convert a string to lower case in Bash?
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The are various ways:
POSIX standard
tr
$ echo "$a" | tr '[:upper:]' '[:lower:]'
hi all
AWK
$ echo "$a" | awk '{print tolower($0)}'
hi all
Non-POSIX
You may run into portability issues with the following examples:
Bash 4.0
$ echo "${a,,}"
hi all...
What's the difference between ISO 8601 and RFC 3339 Date Formats?
ISO 8601 and RFC 3339 seem to be two formats that are common the web. Should I use one over the other? Is one just an extension? Do I really need to care that bad?
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Missing return statement in a non-void method compiles
...ered a situation where a non-void method is missing a return statement and the code still compiles.
I know that the statements after the while loop are unreachable (dead code) and would never be executed. But why doesn't the compiler even warn about returning something? Or why would a language...
Python constructors and __init__
Why are constructors indeed called "Constructors"? What is their purpose and how are they different from methods in a class?
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Express.js - app.listen vs server.listen
... get it. What is the difference between creating an app using Express.js and starting the app listening on port 1234, for example:
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In Python, how do I iterate over a dictionary in sorted key order?
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This is not obvious. In fact, items() creates a list and therefore uses memory, whereas iteritems() essentially does not use memory. What to use mostly depend on the size of the dictionary. Furthermore, the automatic Python 2 to Python 3 conversion tool (2to3) automatically tak...
Difference between static memory allocation and dynamic memory allocation
...would like to know what is the difference between static memory allocation and dynamic memory allocation?
7 Answers
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Intercept page exit event
... page within my system, a user might decide to navigate to another website and in doing so could lose all the edits they have not saved.
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