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What Every Programmer Should Know About Memory?
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The guide in PDF form is at https://www.akkadia.org/drepper/cpumemory.pdf.
It is still generally excellent and highly recommended (by me, and I think by other performance-tuning experts). It would be cool if Ulrich (or anyone else) wrote a 2017 update...
How do I add a linker or compile flag in a CMake file?
I am using the arm-linux-androideabi-g++ compiler. When I try to compile a simple "Hello, World!" program it compiles fine. When I test it by adding a simple exception handling in that code it works too (after adding -fexceptions .. I guess it is disabled by default).
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Python string class like StringBuilder in C#?
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result in very slow running code. In
this article I investigate the
computational performance of various
string concatenation methods.
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How do I get my Python program to sleep for 50 milliseconds?
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90
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Best way to test for a variable's existence in PHP; isset() is clearly broken
...ariables to the global scope whose names were determined by aspects of the HTTP request (GET and POST parameters, and cookies). This can lead to buggy and insecure code, which is why it has been disabled by default since PHP 4.2, released Aug 2000 and removed completely in PHP 5.4, released Mar 2012...
Calculate distance between 2 GPS coordinates
... If anyone, specifically those of you who don't look for end of line comments, is staring at this formula and looking for a unit of distance, the unit is km. :)
– Dylan Knowles
Sep 27 '13 at 18:01
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How can I maintain fragment state when added to the back stack?
...e feeling I'm after the same thing as this question, but I've included a complete code sample to help root out the issue:
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Most efficient method to groupby on an array of objects
...O(n), from the reduce (object assignment is O(1), as is push), whereas the comment is O(n)*O(n) or O(n^2) or at least O(nlgn)
– narthur157
Jul 11 '18 at 10:47
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Remove empty array elements
...back is supplied, all entries of input equal to FALSE will be removed." -- http://php.net/manual/en/function.array-filter.php
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Nested attributes unpermitted parameters
...name, :age, pets_attributes: [:id, :name, :category])
Don't.
Source:
https://github.com/rails/rails/issues/9454#issuecomment-14167664
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