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PHP Foreach Pass by Reference: Last Element Duplicating? (Bug?)

... 170 After the first foreach loop, $item is still a reference to some value which is also being used ...
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round() for float in C++

...in cmath (according to http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3337.pdf) #include <cmath> #include <iostream> int main(int argc, char** argv) { std::cout << "round(0.5):\t" << round(0.5) << std::endl; std::cout << "round(-0.5):\t" << r...
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Write bytes to file

I have a hexadecimal string (e.g 0CFE9E69271557822FE715A8B3E564BE ) and I want to write it to a file as bytes. For example, ...
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Divide a number by 3 without using *, /, +, -, % operators

... x = t; } return y; } int divideby3(int num) { int sum = 0; while (num > 3) { sum = add(num >> 2, sum); num = add(num >> 2, num & 3); } if (num == 3) sum = add(sum, 1); return sum; } As Jim commented this works, because:...
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How to darken a background using CSS?

...t black, faked with gradient */ linear-gradient( rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7) ), /* bottom, image */ url(http://fc02.deviantart.net/fs71/i/2011/274/6/f/ocean__sky__stars__and_you_by_muddymelly-d4bg1ub.png); } Reference...
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Which is better, number(x) or parseFloat(x)?

... same: parseFloat('3'); // => 3 Number('3'); // => 3 parseFloat('1.501'); // => 1.501 Number('1.501'); // => 1.501 parseFloat('1e10'); // => 10000000000 Number('1e10'); // => 10000000000 So as long as you have standard numeric input, there's no difference. However, if your input...
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Cluster analysis in R: determine the optimal number of clusters

... 1024 If your question is how can I determine how many clusters are appropriate for a kmeans analysi...
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Making WPF applications look Metro-styled, even in Windows 7? (Window Chrome / Theming / Theme)

... +100 What I did was creating my own Window and Style. Because I like to have control over everything and I didn't want some external libra...
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How to create NS_OPTIONS-style bitmask enumerations in Swift?

... Swift 3.0 Almost identical to Swift 2.0. OptionSetType was renamed to OptionSet and enums are written lower case by convention. struct MyOptions : OptionSet { let rawValue: Int static let firstOption = MyOptions(rawValue:...
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How to append rows to an R data frame

...sive insight than system.time: library(microbenchmark) microbenchmark(f1(1000), f3(1000), f4(1000), times = 5) # Unit: milliseconds # expr min lq median uq max neval # f1(1000) 1024.539618 1029.693877 1045.972666 1055.25931 1112.769176 5 # f3(1000) ...