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What is __declspec and when do I need to use it?
I have seen instances of __declspec in the code that I am reading. What is it? And when would I need to use this construct?
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Visual Studio support for new C / C++ standards?
I keep reading about C99 and C++11 and all these totally sweet things that are getting added to the language standard that might be nice to use someday. However, we currently languish in the land of writing C++ in Visual Studio.
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Default template arguments for function templates
Why are default template arguments only allowed on class templates? Why can't we define a default type in a member function template? For example:
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Specifically, what's dangerous about casting the result of malloc?
Now before people start marking this a dup, I've read all the following, none of which provide the answer I'm looking for:
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Coding Practices which enable the compiler/optimizer to make a faster program
...act.
Expect to be disappointed and to have to work very hard indeed for small performance improvements. Modern compilers for mature languages such as Fortran and C are very, very good. If you read an account of a 'trick' to get better performance out of code, bear in mind that the compiler writer...
Does Python support short-circuiting?
...circuiting "executed" not printed
1
>>> 1 and fun(1) # fun(1) called and "executed" printed
executed
1
>>> 0 and fun(1) # due to short-circuiting "executed" not printed
0
Note: The following values are considered by the interpreter to mean false:
False None ...
“ImportError: No module named” when trying to run Python script
...the notebook to operate from in your ipython_notebook_config.py file (typically using the c.NotebookManager.notebook_dir setting).
The solution is to provide the python interpreter with the path-to-your-module. The simplest solution is to append that path to your sys.path list. In your notebook, fi...
What are naming conventions for MongoDB?
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Keep'em short: Optimizing Storage of Small Objects, SERVER-863. Silly but true.
I guess pretty much the same rules that apply to relation databases should apply here. And after so many decades there is still no agreement whether RDBMS tables should be named singul...
Create list of single item repeated N times
I want to create a series of lists, all of varying lengths. Each list will contain the same element e , repeated n times (where n = length of the list).
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Selecting multiple columns in a pandas dataframe
...).
df1 = df[['a', 'b']]
Alternatively, if it matters to index them numerically and not by their name (say your code should automatically do this without knowing the names of the first two columns) then you can do this instead:
df1 = df.iloc[:, 0:2] # Remember that Python does not slice inclusive of...