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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
10 Answers
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Officially, what is typename for?
On occasion I've seen some really indecipherable error messages spit out by gcc when using templates... Specifically, I've had problems where seemingly correct declarations were causing very strange compile errors that magically went away by prefixing the typename keyword to the beginning of the...
What's the difference between a Future and a Promise?
What's the difference between Future and Promise ?
They both act like a placeholder for future results, but where is the main difference?
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What is the correct SQL type to store a .Net Timespan with values > 24:00:00?
I am trying to store a .Net TimeSpan in SQL server 2008 R2.
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Difference between \w and \b regular expression meta characters
Can anyone explain the difference between \b and \w regular expression metacharacters? It is my understanding that both these metacharacters are used for word boundaries. Apart from this, which meta character is efficient for multilingual content?
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Simplest code for array intersection in javascript
What's the simplest, library-free code for implementing array intersections in javascript? I want to write
35 Answers
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What is a practical use for a closure in JavaScript?
I'm trying my hardest to wrap my head around JavaScript closures.
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'Static readonly' vs. 'const'
I've read around about const and static readonly fields. We have some classes which contain only constant values. They are used for various things around in our system. So I am wondering if my observation is correct:
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Does using “new” on a struct allocate it on the heap or stack?
When you create an instance of a class with the new operator, memory gets allocated on the heap. When you create an instance of a struct with the new operator where does the memory get allocated, on the heap or on the stack ?
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Start / Stop a Windows Service from a non-Administrator user account
I have a WindowsService named, say, BST. And I need to give a non-Administrator user, UserA, the permissions to Start/Stop this particular service. My service runs on a variety of Windows OS, starting from Windows Server 2003 to Windows 7.
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