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Append an object to a list in R in amortized constant time, O(1)?
... single operation occasionally takes much longer than normal (e.g. if a preallocated buffer is exhausted and occasionally requires resizing to a larger buffer size), as long as the long-term average performance is constant time, we'll still call it O(1).
For comparison, I will also describe "linear...
How do I replace whitespaces with underscore?
...o replace... If you want to replace your other characters with '-' between tokens have the first RE replace with a single space as indicated - i.e. s = re.sub(r"\W", '&nbsp', s) (this may be a shonky formatting issue on StackOverflow: meta.stackexchange.com/questions/105507/…)
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std::cin input with spaces?
...
It doesn't "fail"; it just stops reading. It sees a lexical token as a "string".
Use std::getline:
int main()
{
std::string name, title;
std::cout << "Enter your name: ";
std::getline(std::cin, name);
std::cout << "Enter your favourite movie: ";
std::get...
How to perform Callbacks in Objective-C
...ts delegate, then there would be a retain cycle. It's a good idea in the dealloc method of a class that that has a MyClass instance and is its delegate to clear that delegate reference since it's a weak back pointer. Otherwise if something is keeping the MyClass instance alive, you'll have a danglin...
Appending a vector to a vector [duplicate]
... = orig;
std::copy(v.begin(), v.end(), std::back_inserter(v));
// std::bad_alloc exception is generated
// GOOD, but I can't guarantee it will work with any STL:
v = orig;
v.reserve(v.size()*2);
v.insert(v.end(), v.begin(), v.end());
// Now v contains: { "first", "second", "first", "second" }
// G...
do {…} while(false)
...t way to FORCE a semicolon after the macro invocation, absolutely no other token is allowed to follow.
And another possibility is that there either once was a loop there or iteration is anticipated to be added in the future (e.g. in test-driven development, iteration wasn't needed to pass the tests...
Retrieve a single file from a repository
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wget 'https://github.abc.abc.com/raw/abc/folder1/master/folder2/myfile.py?token=DDDDnkl92Kw8829jhXXoxBaVJIYW-h7zks5Vy9I-wA%3D%3D' -O myfile.py
Curl example:
curl 'https://example.com/raw.txt' > savedFile.txt
share
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Types in MySQL: BigInt(20) vs Int(20)
...111000 (length 39 characters)
If you have INT(20) for system this means allocate in memory minimum 20 bits. But if you'll insert value that bigger than 2^20, it will be stored successfully, only if it's less then INT(32) -> 2147483647 (or 2 * INT(32) -> 4294967295 for UNSIGNED)
Example:
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Is there a way to get the XPath in Google Chrome?
...luate XPath/CSS selectors and highlight matching nodes in the DOM.
Execute tokens $x("some_xpath") or $$("css-selectors") in Console panel, which will both evaluate and validate.
From Elements panel
Press F12 to open up Chrome DevTools.
Elements panel should be opened by default.
Press Ctrl + F t...
What are the advantages of NumPy over regular Python lists?
... (4 for type pointer, 4 for reference count, 4 for value -- and the memory allocators rounds up to 16). A NumPy array is an array of uniform values -- single-precision numbers takes 4 bytes each, double-precision ones, 8 bytes. Less flexible, but you pay substantially for the flexibility of standard...