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How to find out which package version is loaded in R?
...It has 2 versions of R installed. System wide R 2.11 (Debian 6.0) and R 2.14.2 in non-standard location.
12 Answers
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Is “for(;;)” faster than “while (TRUE)”? If not, why do people use it?
... :D
– Chris Cooper
Apr 9 '10 at 22:14
6
@Steven LOL, that is interesting, but then consider that ...
Create or write/append in text file
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348
Try something like this:
$txt = "user id date";
$myfile = file_put_contents('logs.txt', $tx...
How do I sort a vector of pairs based on the second element of the pair?
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EDIT: using c++14, the best solution is very easy to write thanks to lambdas that can now have parameters of type auto. This is my current favorite solution
std::sort(v.begin(), v.end(), [](auto &left, auto &right) {
return left...
'is' versus try cast with null check
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149
Because there's only one cast. Compare this:
if (myObj.myProp is MyType) // cast #1
{
var ...
Most efficient way to remove special characters from string
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24 Answers
24
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How to install XNA game studio on Visual Studio 2012?
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4 Answers
4
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How to get method parameter names?
...s variables, and the defaults provided. ie.
>>> def foo(a, b, c=4, *arglist, **keywords): pass
>>> inspect.getfullargspec(foo)
(['a', 'b', 'c'], 'arglist', 'keywords', (4,))
Note that some callables may not be introspectable in certain implementations of Python. For Example, in...
LINQ Aggregate algorithm explained
... carries forward. etc.
Example 1. Summing numbers
var nums = new[]{1,2,3,4};
var sum = nums.Aggregate( (a,b) => a + b);
Console.WriteLine(sum); // output: 10 (1+2+3+4)
This adds 1 and 2 to make 3. Then adds 3 (result of previous) and 3 (next element in sequence) to make 6. Then adds 6 and 4 t...
Iterator invalidation rules
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C++17 (All references are from the final working draft of CPP17 - n4659)
Insertion
Sequence Containers
vector: The functions insert, emplace_back, emplace, push_back cause reallocation if the new size is greater than the old capacity. Reallocation invalidates all the references, pointers,...