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Is there a standard sign function (signum, sgn) in C/C++?
I want a function that returns -1 for negative numbers and +1 for positive numbers.
http://en.wikipedia.org/wiki/Sign_function
It's easy enough to write my own, but it seems like something that ought to be in a standard library somewhere.
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What is boxing and unboxing and what are the trade offs?
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Boxed values are data structures that are minimal wrappers around primitive types*. Boxed values are typically stored as pointers to objects on the heap.
Thus, boxed values use more memory and take at minimum two memory lookups to access: once to get the pointer, and another to follow that po...
How to automatically select all text on focus in WPF TextBox?
If I call SelectAll from a GotFocus event handler, it doesn't work with the mouse - the selection disappears as soon as mouse is released.
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Git submodule head 'reference is not a tree' error
I have a project with a submodule that is pointing to an invalid commit: the submodule commit remained local and when I try to fetch it from another repo I get:
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Why can't yield return appear inside a try block with a catch?
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I suspect this is a matter of practicality rather than feasibility. I suspect there are very, very few times where this restriction is actually an issue that can't be worked around - but the added complexity in the compiler would be very significant.
There are a ...
How to make layout with View fill the remaining space?
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Answer from woodshy worked for me, and it is simpler than the answer by Ungureanu Liviu since it does not use RelativeLayout.
I am giving my layout for clarity:
<LinearLayout
android:layout_width="fill_parent"
android:layout_height="wrap_content"
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Can I multiply strings in Java to repeat sequences? [duplicate]
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The easiest way in plain Java with no dependencies is the following one-liner:
new String(new char[generation]).replace("\0", "-")
Replace generation with number of repetitions, and the "-" with the string (or char) you want repeated.
All this does is ...
What are OLTP and OLAP. What is the difference between them?
...m don't give me an idea, or my knowledge is too insufficient to understand it.
5 Answers
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Updating packages in Emacs
...he list of packages), and then type U x.
package-refresh-contents unconditionally tries to download a package list from all repos you've added to package-archives; package-archive-contents is non nil if you have already downloaded the package list.
ELPA is the original. I don't think it's really...
Why is React's concept of Virtual DOM said to be more performant than dirty model checking?
...le libraries. Essentially, React knows when to re-render the scene because it is able to observe when this data changes. Dirty checking is slower than observables because you must poll the data at a regular interval and check all of the values in the data structure recursively. By comparison, settin...