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How to check if PHP array is associative or sequential?

...kurO. For the second question (checking whether the array is zero-indexed and sequential), you can use the following function: function isAssoc(array $arr) { if (array() === $arr) return false; return array_keys($arr) !== range(0, count($arr) - 1); } var_dump(isAssoc(['a', 'b', 'c'])); //...
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Why is there huge performance hit in 2048x2048 versus 2047x2047 array multiplication?

...L is always power of 2. The six comes from fact that 2^6 == 64 bytes is standard size of cache line. Now what does this mean? Well it means that if I have address X and address Y and (X >> 6) - (Y >> 6) is divisible by L (i.e. some large power of 2), they will be stored in the same ca...
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What is the difference between log4net and ELMAH?

... ELMAH serves a purpose of tracking errors and exceptions for your web applications and allows you to easily log or view those exceptions via many different mechanisms (SQL, RSS, Twitter, files, email, etc.). If you have no built-in exception handling ELMAH will most ...
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JPA OneToMany not deleting child

I have a problem with a simple @OneToMany mapping between a parent and a child entity. All works well, only that child records are not deleted when I remove them from the collection. ...
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How to use Class in Java?

There's a good discussion of Generics and what they really do behind the scenes over at this question , so we all know that Vector<int[]> is a vector of integer arrays, and HashTable<String, Person> is a table of whose keys are strings and values Person s. However, what stumps me ...
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Vim for Windows - What do I type to save and exit from a file?

...lly typed git commit -a instead of git commit -am "My commit message" , and now I'm viewing my CMD prompt filled with the file version of my commit message ("Please enter the commit message for your..."). I've added my message to the top, but now I can't figure out how to save and leave. I tried ...
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Java - How to create new Entry (key, value)

...ld = this.value; this.value = value; return old; } } And then use it: Map.Entry<String, Object> entry = new MyEntry<String, Object>("Hello", 123); System.out.println(entry.getKey()); System.out.println(entry.getValue()); ...
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What's the absurd function in Data.Void useful for?

...little bit hard, since Haskell is non strict. The general use case is to handle impossible paths. For example simple :: Either Void a -> a simple (Left x) = absurd x simple (Right y) = y This turns out to be somewhat useful. Consider a simple type for Pipes data Pipe a b r = Pure r | A...
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SVN+SSH, not having to do ssh-add every time? (Mac OS)

I know the answer is out there, but I'm pretty Unix-dumb and probably wouldn't recognize the solution if it hit me in the face. ...
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Difference between Big-O and Little-O Notation

What is the difference between Big-O notation O(n) and Little-O notation o(n) ? 4 Answers ...