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arrayfun can be significantly slower than an explicit loop in matlab. Why?

...lution is clearly the fastest, you can see that defining a function to be called for every x entry is a huge overhead. Just explicitly writing out the computation got us factor 5 speedup. I guess this shows that MATLABs JIT compiler does not support inline functions. According to the answer by gnovi...
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SQL Update with row_number()

...able and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator. Instead, you could just have given the CTE a different name as well as added the target column to i...
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Case objects vs Enumerations in Scala

... deal with an Option[Currency] type that would clearly indicate there is really a matching problem and "encourage" the user of the API to sort it out him/herself. To follow up on the other answers here, the main drawbacks of case objects over Enumerations are: Can't iterate over all instances of t...
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In Functional Programming, what is a functor?

...e reading various articles on functional programming, but the authors typically assume the reader already understands the term. Looking around on the web has provided either excessively technical descriptions (see the Wikipedia article ) or incredibly vague descriptions (see the section on Functors...
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How do I concatenate two arrays in C#?

...ays. It seems the only functional purpose for using arrays is for Interop calls (Unmanaged C++). – Levi Fuller Oct 26 '15 at 22:40 1 ...
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Find indices of elements equal to zero in a NumPy array

... As of numpy 1.16, the documentation for numpy.where specifically recommends using numpy.nonzero directly rather than calling where with only one argument. – jirassimok Jul 18 '19 at 21:54 ...
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Iterating over Java collections in Scala

... As of Scala 2.8, all you have to do is to import the JavaConversions object, which already declares the appropriate conversions. import scala.collection.JavaConversions._ This won't work in previous versions though. ...
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Add a column with a default value to an existing table in SQL Server

...ed for Existing Records. If your Column is NOT NULL, then it will automatically use the Default Value     for all Existing Records, whether you specify WITH VALUES or not. How Inserts work with a Default-Constraint: If you insert a Record into SomeTable and do not Specify SomeCol's value, then it...
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How to check if type of a variable is string?

...atter, because Python 3.x is not meant to be compatible with Python 2.x at all. – netcoder Jul 15 '13 at 17:45 2 ...
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Volatile vs. Interlocked vs. lock

... Worst (won't actually work) Change the access modifier of counter to public volatile As other people have mentioned, this on its own isn't actually safe at all. The point of volatile is that multiple threads running on multiple CPUs can and...