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Why doesn't Python have a sign function?
I can't understand why Python doesn't have a sign function. It has an abs builtin (which I consider sign 's sister), but no sign .
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Concept of void pointer in C programming
Is it possible to dereference a void pointer without type-casting in the C programming language?
15 Answers
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Keyword not supported: “data source” initializing Entity Framework Context
I'm initializing Entity Framework Object context, and this gives me the keyword not supported error:
6 Answers
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Read an Excel file directly from a R script
...do this directly is that you may want to examine the spreadsheet to see if it has glitches (weird headers, multiple worksheets [you can only read one at a time, although you can obviously loop over them all], included plots, etc.). But for a well-formed, rectangular spreadsheet with plain numbers a...
How do you copy the contents of an array to a std::vector in C++ without looping?
...sing. Since I don't know how many times my function will be called before it is time to process the data, I need a dynamic storage structure, so I chose a std::vector . I don't want to have to do the standard loop to push_back all the values individually, it would be nice if I could just copy i...
How to use UIScrollView in Storyboard
I have a scroll view with content that is 1000px tall and would like to be able to lay it out for easy design on the storyboard.
I know it can be done programmatically but I really want to be able to see it visually. Every time I put a scroll view on a view controller it won't scroll. Is it possib...
How to find out client ID of component for ajax update/render? Cannot find component with expression
...to a <p:tab> of a <p:tabView> residing in a <p:layoutUnit> of a <p:layout> . Here is the inner part of the code (starting from p:tab component); the outer part is trivial.
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Fastest way to reset every value of std::vector to 0
...t every value of a std::vector<int> to 0 and keeping the vectors initial size ?
6 Answers
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What is a mixin, and why are they useful?
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A mixin is a special kind of multiple inheritance. There are two main situations where mixins are used:
You want to provide a lot of optional features for a class.
You want to use one particular feature in a lot of different classes.
For an example of number one,...
Why is address zero used for the null pointer?
...: I am adviced to set pointers to zero after freeing their memory, because it means freeing the pointer again isn't dangerous; when I call malloc it returns a pointer with the value zero if it can't get me memory; I use if (p != 0) all the time to make sure passed pointers are valid, etc.
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