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Why does Math.round(0.49999999999999994) return 1?
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Summary
In Java 6 (and presumably earlier), round(x) is implemented as floor(x+0.5).1 This is a specification bug, for precisely this one pathological case.2 Java 7 no longer mandates this broken implementation.3
The problem
0.5+0.49999999...
how to rotate a bitmap 90 degrees
There is a statement in android canvas.drawBitmap(visiblePage, 0, 0, paint);
10 Answers
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Why does this code using random strings print “hello world”?
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When an instance of java.util.Random is constructed with a specific seed parameter (in this case -229985452 or -147909649), it follows the random number generation algorithm beginning with that seed value.
Every Random constructed with the same seed will ...
Elastic Search: how to see the indexed data
I had a problem with ElasticSearch and Rails, where some data was not indexed properly because of attr_protected. Where does Elastic Search store the indexed data? It would be useful to check if the actual indexed data is wrong.
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What is the difference between
... edited Aug 11 at 9:09
Alexandr Nil
14111 gold badge55 silver badges1010 bronze badges
answered Nov 3 '11 at 14:44
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Ruby Gem install Json fails on Mavericks and Xcode 5.1 - unknown argument: '-multiply_definedsuppres
I was trying run gem install json and got the following error
10 Answers
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Multiple aggregations of the same column using pandas GroupBy.agg()
Is there a pandas built-in way to apply two different aggregating functions f1, f2 to the same column df["returns"] , without having to call agg() multiple times?
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Is SQL or even TSQL Turing Complete?
...e programming languages, so that's kinda cheating).
In this set of slides Andrew Gierth proves that with CTE and Windowing SQL is Turing Complete, by constructing a cyclic tag system, which has been proved to be Turing Complete. The CTE feature is the important part however -- it allows you to crea...
PostgreSQL LIKE query performance variations
...text indexes is not for the LIKE operator at all, it has its own operators and doesn't work for arbitrary strings. It operates on words based on dictionaries and stemming. It does support prefix matching for words, but not with the LIKE operator:
Get partial match from GIN indexed TSVECTOR column
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Combining two expressions (Expression)
I have two expressions of type Expression<Func<T, bool>> and I want to take to OR, AND or NOT of these and get a new expression of the same type
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