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What is the difference between #import and #include in Objective-C?
... decent header files protect themselves against this anyway, so it's not really that much of a benefit.
Basically, it's up to you to decide which you want to use. I tend to #import headers for Objective-C things (like class definitions and such) and #include standard C stuff that I need. For exampl...
Pandas aggregate count distinct
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Just adding to the answers already given, the solution using the string "nunique" seems much faster, tested here on ~21M rows dataframe, then grouped to ~2M
%time _=g.agg({"id": lambda x: x.nunique()})
CPU times: user 3min 3s, sys: 2.94 s, total: 3min 6s
Wall time: 3min 20s
%time _=g.ag...
system(“pause”); - Why is it wrong?
...upon because it's a platform-specific hack that has nothing to do with actually learning programming, but instead to get around a feature of the IDE/OS - the console window launched from Visual Studio closes when the program has finished execution, and so the new user doesn't get to see the output o...
When should I write the keyword 'inline' for a function/method?
...cade later the compiler needs no such hints. Not to mention humans are usually wrong when it comes to optimizing code, so most compilers flat out ignore the 'hint'.
static - the variable/function name cannot be used in other translation units. Linker needs to make sure it doesn't accidentally us...
JComboBox Selection Change Listener?
...x();
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Object selectedObject = myComboBox.getSelectedItem();
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String selectedValue = myComboBox.getSelectedValue().toString();
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Is there a way for multiple processes to share a listening socket?
...POSIX type OS), using fork() will cause the forked child to have copies of all the parent's file descriptors. Any that it does not close will continue to be shared, and (for example with a TCP listening socket) can be used to accept() new sockets for clients. This is how many servers, including Apac...
How to get svn remote repository URL?
...output only the remote url. To get rid of the newline at the end, add this extra option:
svn info --show-item=url --no-newline
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express 4.0 , express-session with odd warning message
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Works for me, maybe the session needed just some extra settings. Thanks
– martinhajny
Oct 10 '18 at 8:54
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Remove a cookie
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@machineaddict unset($_COOKIE['Hello']); is actually important if you might check the cookie somewhere later in the code.
– Andreas Hultgren
Jun 13 '14 at 12:08
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Are there benefits of passing by pointer over passing by reference in C++?
...inter types is not possible (pointers are builtin types). So you can't do string s = &str1 + &str2; using pointers.
No 0 values possible -> Called function doesn't have to check for them
Reference to const also accepts temporaries: void f(const T& t); ... f(T(a, b, c));, pointers ca...