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What is the difference between quiet NaN and signaling NaN?
...ented in software. A signalling NaN will produce a signal, usually in the form of exception from the FPU. Whether the exception is thrown depends on the state of the FPU.
C++11 adds a few language controls over the floating-point environment and provides standardized ways to create and test for N...
Getters \ setters for dummies
...eir silverlight run everywhere, so I have to program everything twice, one for SL and one for rest of the world :)
– Akash Kava
Mar 22 '11 at 16:19
2
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Stack smashing detected
I am executing my a.out file. After execution the program runs for some time then exits with the message:
9 Answers
...
capturing self strongly in this block is likely to lead to a retain cycle
...d by self.
You can get around this by creating a weak reference to self before accessing timerDisp inside your block:
__weak typeof(self) weakSelf = self;
[player addPeriodicTimeObserverForInterval:CMTimeMakeWithSeconds(0.1, 100)
queue:nil
...
Is there a performance difference between a for loop and a for-each loop?
What, if any, is the performance difference between the following two loops?
16 Answers
...
Get last result in interactive Python shell
... It only works in the interactive shell, though. Don't rely on it for scripts.
– John Fouhy
Oct 14 '08 at 4:54
7
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Django ManyToMany filter()
... style filters in the many-to-many and many-to-one tests. Here is syntax for your specific problem:
users_in_1zone = User.objects.filter(zones__id=<id1>)
# same thing but using in
users_in_1zone = User.objects.filter(zones__in=[<id1>])
# filtering on a few zones, by id
users_in_zones...
How to match “any character” in regular expression?
...
That's some very useful information! I assumed . would match newlines. I'm glad I read your answer, I need to use that!
– Ben Kane
Sep 4 '13 at 14:30
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How to get the original value of an attribute in Rails
...
Before rails 5.1
Appending _was to your attribute will give you the previous value.
For rails 5.1+
Copied from Lucas Andrade's answer below: https://stackoverflow.com/a/50973808/9359123
Appending _was is deprecated in ra...
Django select only rows with duplicate field values
... .filter(id__count__gt=1)
Literal.objects.filter(name__in=[item['name'] for item in dupes])
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