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Java Reflection Performance
Does creating an object using reflection rather than calling the class constructor result in any significant performance differences?
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Difference between decimal, float and double in .NET?
...n a decimal form, and expect exact results in decimal representations; not all decimal numbers are exactly representable in binary floating point – 0.1, for example – so if you use a binary floating point value you'll actually get an approximation to 0.1. You'll still get approximations when usi...
Checking length of dictionary object [duplicate]
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What I do is use Object.keys() to return a list of all the keys and then get the length of that
Object.keys(dictionary).length
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Unpacking array into separate variables in JavaScript
...nd I've done it before. I just can't remember how, or what exactly it was called.
7 Answers
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Why does scanf() need “%lf” for doubles, when printf() is okay with just “%f”?
...cross-use" %lf with float or %f with double.
But there's no reason to actually do it in practice. Don't use %f to printf arguments of type double. It is a widespread habit born back in C89/90 times, but it is a bad habit. Use %lf in printf for double and keep %f reserved for float arguments.
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CSS does the width include the padding?
...width: 10em; padding: 2em; border: 1em; }
would be 10em wide.
In contrast, all standards-fearing browsers default to the "content-box" box model. In this model, the width of an element does not include padding or borders. For example:
#foo { width: 10em; padding: 2em; border: 1em; }
will actually be...
Visual Studio 2012 Express is suddenly “incompatible with this version of Windows”?
...e same message on Visual Studio 2012 Premium (on PC where Windows 7 re-installed in last month) - the suggested fix was "Update for Microsoft Visual Studio 2012 (KB2781514)" which seems to have fixed it
www.microsoft.com/en-us/download/details.aspx?id=36020
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Difference between the Facade, Proxy, Adapter and Decorator design patterns? [closed]
...o a new interface. In the case of the former, multiple inheritance is typically employed. In the latter case, the object is wrapped by a conforming adapter object and passed around. The problem we are solving here is that of non-compatible interfaces.
Facade is more like a simple gateway to a compl...
How to store arrays in MySQL?
...raberry"
2 | "banana"
2 | "apple"
When you want to retrieve a person and all of their fruit you can do something like this:
SELECT p.*, f.*
FROM person p
INNER JOIN person_fruit pf
ON pf.person_id = p.id
INNER JOIN fruits f
ON f.fruit_name = pf.fruit_name
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How can I output UTF-8 from Perl?
...sults. I'm using Mac OS X 10.5 (Leopard), and I'm editing with TextMate. All of my settings for both my editor and operating system are defaulted to writing files in utf-8 format.
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