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How to pull a random record using Django's ORM?
... self.aggregate(count=Count('id'))['count']
random_index = randint(0, count - 1)
return self.all()[random_index]
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CMake: Print out all accessible variables in a script
...riableNames)
foreach (_variableName ${_variableNames})
if (ARGV0)
unset(MATCHED)
string(REGEX MATCH ${ARGV0} MATCHED ${_variableName})
if (NOT MATCHED)
continue()
endif()
endif()
message(STATUS "${_variableNa...
Showing Difference between two datetime values in hours
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120
I think you're confused because you haven't declared a TimeSpan you've declared a TimeSpan? whic...
What is the ellipsis (…) for in this method signature?
...id2, jid78_a, someOtherJid);
See more here:
http://java.sun.com/j2se/1.5.0/docs/guide/language/varargs.html
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Is returning by rvalue reference more efficient?
...O to omit doing a move or copy altogether. I recommend you to read BoostCon09 Rvalue References 101 which explains the matter, and how (N)RVO happens to interact with this.
Your case of returning an rvalue reference would be a good idea in other occasions. Imagine you have a getAB() function whic...
SQLite table constraint - unique on multiple columns
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answered Apr 23 '10 at 20:50
Ayman HouriehAyman Hourieh
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jQuery .scrollTop(); + animation
... first I used an if statement to see if the top of the page was not set to 0. Then if it's not 0 I animate the page to scroll to the top.
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How does one make random number between range for arc4random_uniform()?
...m(UInt32). I attempted using the range of (1..7) to avoid randomly getting 0 however that returned an error which I didn't enjoy too much. I tried to do this:
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What does “abstract over” mean?
... numbers under a single symbol ns:
def sumOf(ns: List[Int]) = ns.foldLeft(0)(_ + _)
And we don't particularly care that it's a List either. List is a specific type constructor (takes a type and returns a type), but we can abstract over the type constructor by specifying which essential characteri...
How to capture UIView to UIImage without loss of quality on retina display
... UIGraphicsBeginImageContextWithOptions (as documented on this page). Pass 0.0 for scale (the third argument) and you'll get a context with a scale factor equal to that of the screen.
UIGraphicsBeginImageContext uses a fixed scale factor of 1.0, so you're actually getting exactly the same image on ...