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Performance of Java matrix math libraries? [closed]
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Using Jama with Java, the time taken was 50 seconds.
Using Colt and Parallel Colt with Java, the time taken was 150 seconds!
Using JBLAS with Java, the time taken was again around 4 seconds as JBLAS uses multithreaded ATLAS.
So for me it was clear that the Java libraries didn't perform too wel...
How do I use a custom Serializer with Jackson?
...ations of non-essential methods (i.e. everything but actual serialization call).
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In Java, how do I convert a byte array to a string of hex digits while keeping leading zeros? [dupli
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When I called Integer.toHexString((byte)0xff) it returned "ffffffff" because of sign extension. So one might need to take the last two characters of the returned string.
– Marvo
Jul 27 '12 at 2...
Creating a comma separated list from IList or IEnumerable
...;T> source)
{
return new List<T>(source).ToArray();
}
Then call it like this:
IEnumerable<string> strings = ...;
string[] array = Helpers.ToArray(strings);
You can then call string.Join. Of course, you don't have to use a helper method:
// C# 3 and .NET 3.5 way:
string joine...
Converting Mercurial folder to a Git repository
... naXanaXa
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Calling virtual functions inside constructors
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Calling virtual functions from a constructor or destructor is dangerous and should be avoided whenever possible. All C++ implementations should call the version of the function defined at the level of the hierarchy in the cur...
MySQL Error 1093 - Can't specify target table for update in FROM clause
... criteria. This will cause MySQL to see the table as two different things, allowing destructive changes to go ahead.
UPDATE tbl AS a
INNER JOIN tbl AS b ON ....
SET a.col = b.col
Alternatively, try nesting the subquery deeper into a from clause ...
If you absolutely need the subquery, there's a ...
In Python, how to display current time in readable format
...e.g., -0400. %Z gives you current timezone name (or abbreviation) automatically. Python doesn't support %l, you could use %I instead.
– jfs
Dec 14 '13 at 19:30
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Writing a dict to txt file and reading it back?
...al() will evaluate any string, and if someone tricked you into running a really tricky string, something bad might happen. In this case, you are just running eval() on your own file, so it should be okay.
But because eval() is useful, someone made an alternative to it that is safer. This is calle...
How to escape special characters in building a JSON string?
...Tab
\" Double quote
\\ Backslash character
However, even if it is totally contrary to the spec, the author could use \'.
This is bad because :
It IS contrary to the specs
It is no-longer JSON valid string
But it works, as you want it or not.
For new readers, always use a double quote...