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SQL left join vs multiple tables on FROM line?
...//en.wikipedia.org/wiki/SQL. The complete standard can be viewed at http://www.contrib.andrew.cmu.edu/~shadow/sql/sql1992.txt .
It took many years before database companies adopted the SQL-92 standard.
So the reason why the second method is preferred, it is the SQL standard according the ANSI and ...
How do I represent a hextile/hex grid in memory?
...ver them in the Relationships Between Parts section of my grids article at www-cs-students.stanford.edu/~amitp/game-programming/grids (the diagrams are for square grids but the table includes the formulas for axial hex grids also)
– amitp
Jun 7 '13 at 0:58
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How Scalable is SQLite? [closed]
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Have you read this SQLite docs - http://www.sqlite.org/whentouse.html ?
SQLite usually will work great as the
database engine for low to medium
traffic websites (which is to say,
99.9% of all websites). The amount of web traffic that SQLite can handle
d...
Cooler ASCII Spinners? [closed]
...⠄⡀⢀⠠⠐⠈ The entire braille block, even in random order http://www.fileformat.info/info/unicode/block/braille_patterns/images.htm
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Do any JVM's JIT compilers generate code that uses vectorized floating point instructions?
... could write OpenCl kernel to do the computing and run it from java http://www.jocl.org/.
Code can be run on CPU and/or GPU and OpenCL language supports also vector types so you should be able to take explicitly advantage of e.g. SSE3/4 instructions.
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Formula to determine brightness of RGB color
...ce (relative)
0.2126 * R + 0.7152 * G + 0.0722 * B
2nd picture - http://www.w3.org/TR/AERT#color-contrast
0.299 * R + 0.587 * G + 0.114 * B
3rd picture - HSP Color Model
sqrt(0.299 * R^2 + 0.587 * G^2 + 0.114 * B^2)
4th picture - WCAG 2.0 SC 1.4.3 relative luminance and contrast ratio form...
What is the difference between PS1 and PROMPT_COMMAND
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From the GNU Bash doc page: http://www.gnu.org/software/bash/manual/bashref.html
PROMPT_COMMAND
If set, the value is interpreted as a command to execute before
the printing of each primary prompt ($PS1).
I never used it, but I could have used this b...
What is the common header format of Python files?
...very simple documentation. It can fill multiple lines.
See also: https://www.python.org/dev/peps/pep-0263/
If you just write a class in each file, you don't even need the documentation (it would go inside the class doc).
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How to map a composite key with JPA and Hibernate?
...quals(that.getName()). The first will fail, if that is a proxy.
http://www.laliluna.de/jpa-hibernate-guide/ch06s06.html
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return, return None, and no return at all?
...bar(x):
if x < 0:
return
return math.sqrt(x)
https://www.python.org/dev/peps/pep-0008/#programming-recommendations
Basically, if you ever return non-None value in a function, it means the return value has meaning and is meant to be caught by callers. So when you return None,...