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Is 'switch' faster than 'if'?
Is a switch statement actually faster than an if statement?
12 Answers
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What is the purpose of python's inner classes?
...dden from the outside world.
More readable, maintainable code: Nesting small classes within top-level classes places the code closer to where it is used.
The main advantage is organization. Anything that can be accomplished with inner classes can be accomplished without them.
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Sending HTTP POST Request In Java
...alue(), "UTF-8"));
byte[] out = sj.toString().getBytes(StandardCharsets.UTF_8);
int length = out.length;
We can then attach our form contents to the http request with proper headers and send it.
http.setFixedLengthStreamingMode(length);
http.setRequestProperty("Content-Type", "application/x-www-f...
How to reshape data from long to wide format
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The reshape comments and similar argument names aren't all that helpful. However, I have found that for long to wide, you need to provide data = your data.frame, idvar = the variable that identifies your groups, v.names = the variables that will become multiple columns in wide f...
'printf' vs. 'cout' in C++
...letely on operator overloading, so there is no issue with custom formats - all you do is define a subroutine taking std::ostream as the first argument and your type as second. As such, there are no namespace problems - as long you have a class (which isn't limited to one character), you can have wor...
SQL Server Installation - What is the Installation Media Folder?
I am installing SQL Server 2008. I have installed .NET framework 3.5.
Then I got folder SQL Server 2008 and performed following steps-
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What's the idiomatic syntax for prepending to a short python list?
... @MattM. If you insert at the front of a list, python has to move all the other items one space forwards, lists can't "make space at the front". collections.deque (double ended queue) has support for "making space at the front" and is much faster in this case.
– fejfo
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Queue.Queue vs. collections.deque
...nd collections.deque serve different purposes. Queue.Queue is intended for allowing different threads to communicate using queued messages/data, whereas collections.deque is simply intended as a datastructure. That's why Queue.Queue has methods like put_nowait(), get_nowait(), and join(), whereas co...
Getting the first character of a string with $str[0]
...am just not sure whether this is 'good practice', as that notation is generally used with arrays. This feature doesn't seem to be very well documented so I'm turning to you guys to tell me if it's all right – in all respects – to use this notation?
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How to download Xcode DMG or XIP file?
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For Xcode 9, I am told that I am not allowed to view that page. What shall I do?
– Mr. Xcoder
Jun 6 '17 at 18:45
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