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What breaking changes are introduced in C++11?
...+11 that will cause some old code to stop compiling: the introduction of explicit operator bool() in the standard library, replacing old instances of operator void*() . Granted, the code that this will break is probably code that should not have been valid in the first place, but it's still a bre...
How to install Java SDK on CentOS?
I have CentOS 5, but I don't know the steps to install Java SDK on Linux.
12 Answers
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Select by partial string from a pandas DataFrame
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Since str.* methods treat the input pattern as a regular expression, you can use df[df['A'].str.contains("Hello|Britain")]
– Garrett
Jun 27 '13 at 19:20
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What languages are Windows, Mac OS X and Linux written in?
I was just wondering who knows what programming languages Windows, Mac OS X and Linux are made up from and what languages are used for each part of the OS (ie: Kernel, plug-in architecture, GUI components, etc).
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How to Sort a List by a property in the object
...e Sort method, passing a Comparison<T> delegate:
objListOrder.Sort((x, y) => x.OrderDate.CompareTo(y.OrderDate));
If you prefer to create a new, sorted sequence rather than sort in-place then you can use LINQ's OrderBy method, as mentioned in the other answers.
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Deep null checking, is there a better way?
...of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note that there is still some debate over the exact syntactic and semantic analysis of the operator.
Update (July 2015): Visual Studio 2015 has been released and ships with a C# compiler that supp...
C/C++ NaN constant (literal)?
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Or you can compare the number to itself – x == x returns false iff x is NaN.
– Archie
May 22 '13 at 12:10
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Are members of a C++ struct initialized to 0 by default?
...arent p = {}; // value initializes all members
The second will make p.s.{x,y} zero. You cannot use these aggregate initializer lists if you've got constructors in your struct. If that is the case, you will have to add proper initalization to those constructors
struct Snapshot {
int x;
dou...
How to use Boost in Visual Studio 2010
What is a good step by step explanation on how to use the Boost library in an empty project in Visual Studio?
13 Answers
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How to avoid scientific notation for large numbers in JavaScript?
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There's Number.toFixed, but it uses scientific notation if the number is >= 1e21 and has a maximum precision of 20. Other than that, you can roll your own, but it will be messy.
function toFixed(x) {
if (Math.abs(x) < 1.0) {
var e ...