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Map implementation with duplicate keys
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You are searching for a multimap, and indeed both commons-collections and Guava have several implementations for that. Multimaps allow for multiple keys by maintaining a collection of values per key, i.e. you can put a single object into the map, but you retrieve a coll...
How to Correctly Use Lists in R?
Brief background: Many (most?) contemporary programming languages in widespread use have at least a handful of ADTs [abstract data types] in common, in particular,
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How to calculate an angle from three points? [closed]
...* P13))
where P12 is the length of the segment from P1 to P2, calculated by
sqrt((P1x -
P2x)2 +
(P1y -
P2y)2)
share
edited Aug 25 '16 at 13:45
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Javascript: best Singleton pattern [duplicate]
... // ...
}
}
console.log(new Singleton() === new Singleton());
Best solution found:
http://code.google.com/p/jslibs/wiki/JavascriptTips#Singleton_pattern
function MySingletonClass () {
if (arguments.callee._singletonInstance) {
return arguments.callee._singletonInstance;
}
a...
What does {0} mean when initializing an object?
When {0} is used to initialize an object, what does it mean? I can't find any references to {0} anywhere, and because of the curly braces Google searches are not helpful.
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Python strftime - date without leading 0?
...ython strftime , is there a way to remove the first 0 of the date if it's before the 10th, ie. so 01 is 1 ? Can't find a % thingy for that?
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Finding index of character in Swift String
...n't find the solution.
String doesn't implement RandomAccessIndexType. Probably because they enable characters with different byte lengths. That's why we have to use string.characters.count (count or countElements in Swift 1.x) to get the number of characters. That also applies to positions. The _p...
Update multiple columns in SQL
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The "tiresome way" is standard SQL and how mainstream RDBMS do it.
With a 100+ columns, you mostly likely have a design problem... also, there are mitigating methods in client tools (eg generation UPDATE statements) or by using ORMs
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`static` keyword inside function?
... looking at the source for Drupal 7, and I found some things I hadn't seen before. I did some initial looking in the php manual, but it didn't explain these examples.
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CALL command vs. START with /WAIT option
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For exe files, I suppose the differences are nearly unimportant.
But to start an exe you don't even need CALL.
When starting another batch it's a big difference,
as CALL will start it in the same window and the called batch has access to the same variable context.
So it can also change...