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Select multiple columns in data.table by their numeric indices
How can we select multiple columns using a vector of their numeric indices (position) in data.table ?
5 Answers
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Get the closest number out of an array
I have a number from minus 1000 to plus 1000 and I have an array with numbers in it. Like this:
20 Answers
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Transport endpoint is not connected
FUSE is constantly (every 2 - 3 days) giving me this Transport endpoint is not connected error on my mount point and the only thing that seems to fix it is rebooting.
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Get nth character of a string in Swift programming language
How can I get the nth character of a string? I tried bracket( [] ) accessor with no luck.
45 Answers
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Where does 'Hello world' come from?
' hello, world ' is usually the first example for any programming language. I've always wondered where this sentence came from and where was it first used.
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Most efficient way to prepend a value to an array
Assuming I have an array that has a size of N (where N > 0 ), is there a more efficient way of prepending to the array that would not require O(N + 1) steps?
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Understanding the difference between Object.create() and new SomeFunction()
I recently stumbled upon the Object.create() method in JavaScript, and am trying to deduce how it is different from creating a new instance of an object with new SomeFunction() , and when you would want to use one over the other.
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How do you remove duplicates from a list whilst preserving order?
Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this:
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Does the C++ standard mandate poor performance for iostreams, or am I just dealing with a poor imple
Every time I mention slow performance of C++ standard library iostreams, I get met with a wave of disbelief. Yet I have profiler results showing large amounts of time spent in iostream library code (full compiler optimizations), and switching from iostreams to OS-specific I/O APIs and custom buffer...
How can I cast int to enum?
How can an int be cast to an enum in C#?
31 Answers
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