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Is there a fixed sized queue which removes excessive elements?

...ixed size. When I add an element and the queue is full, it should automatically remove the oldest element. 16 Answers ...
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How to do a safe join pathname in ruby?

... One thing to note. Ruby uses a "/" for file separator on all platforms, including Windows, so you don't actually need use different code for joining things together on different platforms. "C:/tmp/1.text" should work fine. File.join() is your friend for joining paths together. p...
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how do I insert a column at a specific column index in pandas?

... If you want a single value for all rows: df.insert(0,'name_of_column','') df['name_of_column'] = value Edit: You can also: df.insert(0,'name_of_column',value) share ...
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Why are these constructs using pre and post-increment undefined behavior?

... concept of undefined behavior, i.e. some language constructs are syntactically valid but you can't predict the behavior when the code is run. As far as I know, the standard doesn't explicitly say why the concept of undefined behavior exists. In my mind, it's simply because the language designers w...
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Why should C++ programmers minimize use of 'new'?

... There are two widely-used memory allocation techniques: automatic allocation and dynamic allocation. Commonly, there is a corresponding region of memory for each: the stack and the heap. Stack The stack always allocates memory in a sequential fashion. It c...
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How to calculate an angle from three points? [closed]

... handful of languages use a caret for 'power of', so if you don't want to call it arcos, please just type cos⁻¹. (If you're using a commercial operating system that makes it difficult to type exponents, I expect there would be keycaps applications you could buy, or maybe a browser plug-in you cou...
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Quick search on filename

... To search only recent files: ctrl+E To search all files: shift + shift share | improve this answer | follow | ...
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How to fix .pch file missing on build?

...tom of the drop-down menu. At the top left of the Properties Pages, select All Configurations from the drop-down menu. Open the C/C++ tree and select Precompiled Headers Precompiled Header: Select Use (/Yu) Fill in the Precompiled Header File field. Standard is stdafx.h Click Okay If you do not have...
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How do I run only specific tests in Rspec?

...onfiguration option treat_symbols_as_metadata_keys_with_true_values, which allows you to do: describe "Awesome feature", :awesome do where :awesome is treated as if it were :awesome => true. Also see this answer for how to configure RSpec to automatically run 'focused' tests. This works especi...
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Side-by-side plots with ggplot2

...wilke below and this vignette for an equivalent approach; but the function allows finer controls on plot location and size, based on this vignette. share | improve this answer | ...