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New Array from Index Range Swift
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Pedantic point, but this isn't really casting the Slice to an Array, but rather creating a new array from a slice. A cast would use the as operator: numbers as Array which would result in an error.
– j b
Jun 10 '14 at 9...
How can you dynamically create variables via a while loop? [duplicate]
I want to create variables dynamically via a while loop in Python. Does anyone have any creative means of doing this?
8 Ans...
Insert picture into Excel cell [closed]
... appear on hover over.
Microsoft Office 365 (2019) introduced new things called comments and renamed the old comments as "notes". Therefore in the steps above do New Note instead of Insert Comment. All other steps remain the same and the functionality still exists.
There is also a $20 product fo...
Best way to give a variable a default value (simulate Perl ||, ||= )
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In PHP 7 we finally have a way to do this elegantly. It is called the Null coalescing operator. You can use it like this:
$name = $_GET['name'] ?? 'john doe';
This is equivalent to
$name = isset($_GET['name']) ? $_GET['name']:'john doe'...
Purpose of Python's __repr__
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__repr__ should return a printable representation of the object, most likely one of the ways possible to create this object. See official documentation here. __repr__ is more for developers while __str__ is for end users.
A ...
How can i tell if an object has a key value observer attached
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Put a try catch around your removeObserver call
@try{
[someObject removeObserver:someObserver forKeyPath:somePath];
}@catch(id anException){
//do nothing, obviously it wasn't attached because an exception was thrown
}
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How to convert nanoseconds to seconds using the TimeUnit enum?
... This answer is now wrong - convert() and the toFoo() methods all return longs now docs.oracle.com/javase/6/docs/api/java/util/concurrent/…
– Riking
Jul 30 '13 at 1:58
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PHP mail function doesn't complete sending of e-mail
... one you need to run through the checklist below to find any potential pitfalls you may be encountering.
Make sure error reporting is enabled and set to report all errors
Error reporting is essential to rooting out bugs in your code and general errors that PHP encounters. Error reporting needs to ...
What is the 'override' keyword in C++ used for? [duplicate]
... removed (not alternated). This is useful if the subclass is expecting a callback but it will never happen due to the library change, etc.
– Hei
Mar 11 '18 at 5:32
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How do I get the row count of a pandas DataFrame?
...[0].count()", "len(data.index)"],
xlabel="data rows"
)
EDIT: As @Dan Allen noted in the comments len(df.index) and df[0].count() are not interchangeable as count excludes NaNs,
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