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Expansion of variables inside single quotes in a command in Bash
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answered Dec 10 '12 at 14:00
Jo SoJo So
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Performance of Java matrix math libraries? [closed]
.... I've compared some of these libraries. I attempted to matrix multiply a 3000 by 3000 matrix of doubles with itself. The results are as follows.
Using multithreaded ATLAS with C/C++, Octave, Python and R, the time taken was around 4 seconds.
Using Jama with Java, the time taken was 50 seconds.
U...
Comma in C/C++ macro
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ecatmurecatmur
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Hashset vs Treeset
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answered Dec 16 '10 at 18:59
sactiwsactiw
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Java: how do I get a class literal from a generic type?
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Karthik
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answered Mar 5 '10 at 23:39
cletuscletus
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What are the lesser known but useful data structures?
...ries, also known as prefix-trees or crit-bit trees, have existed for over 40 years but are still relatively unknown. A very cool use of tries is described in "TRASH - A dynamic LC-trie and hash data structure", which combines a trie with a hash function.
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Remove Identity from a column in a table
We have a 5GB table (nearly 500 million rows) and we want to remove the identity property on one of the column, but when we try to do this through SSMS - it times out.
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CSS3 box-sizing: margin-box; Why not?
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Couldn't you use width: calc(50% - 24px); for your cols? Then set your margins.
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No visible cause for “Unexpected token ILLEGAL”
...ible character in the code, right after the semicolon. It's the Unicode U+200B Zero-width space character (a.k.a. ZWSP, HTML entity ​). That character is known to cause the Unexpected token ILLEGAL JavaScript syntax error.
And where did it come from?
I can't tell for sure, but my bet is on...
What's a concise way to check that environment variables are set in a Unix shell script?
...oughts on this discussion? https://github.com/koalaman/shellcheck/issues/380#issuecomment-145872749
The gist of the discussion is:
… However, when I shellcheck it (with version 0.4.1), I get this message:
In script.sh line 13:
: ${FOO:?"The environment variable 'FOO' must be set and non-empty"}...