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How does the NSAutoreleasePool autorelease pool work?
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Yes, your second code snippit is perfectly valid.
Every time -autorelease is sent to an object, it is added to the inner-most autorelease pool. When the pool is drained, it simply sends -release to all the objects in the pool.
Autorelease pools are simply a convenience that allow...
Cosine Similarity between 2 Number Lists
...modules (math, etc) (and the least modules as possible, at that, to reduce time spent).
13 Answers
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Is 'float a = 3.0;' a correct statement?
....42; }
Here the compiler will emit a conversion (that you will pay at runtime) for each returned value. To avoid it you should declare:
float foo(float x) { return x * 0.42f; } // OK, no conversion required
To avoid bugs when comparing results:
e.g. the following comparison fails :
float x = 4...
How to remove all null elements from a ArrayList or String Array?
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Time complexity of List.removeAll() is n^2. Just saying.
– Hemanth
Feb 3 '16 at 14:05
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How to concatenate two MP4 files using FFmpeg?
I'm trying to concatenate two mp4 files using ffmpeg. I need this to be an automatic process hence why I chose ffmpeg. I'm converting the two files into .ts files and then concatenating them and then trying to encode that concated .ts file. The files are h264 and aac encoded and I'm hoping to kee...
Is it expensive to use try-catch blocks even if an exception is never thrown?
...t no expense at all. Instead of doing the work of setting up the try at runtime, the code's metadata is structured at compile time such that when an exception is thrown, it now does a relatively expensive operation of walking up the stack and seeing if any try blocks exist that would catch this exce...
JOIN queries vs multiple queries
...mark a server under load, however, in most cases, joins will take more CPU time vs PK queries, and often causes more network overhead as well.
– mindplay.dk
May 8 '15 at 19:06
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When should I use uuid.uuid1() vs. uuid.uuid4() in python?
...sions (under the assumption you do not create too many of them at the same time). I wouldn't use it if it's important that there's no connection between the uuid and the computer, as the mac address gets used to make it unique across computers.
You can create duplicates by creating more than 214 uu...
Java String split removed empty values
...d you can find (emphasis mine)
The limit parameter controls the number of times the pattern is applied and therefore affects the length of the resulting array.
If the limit n is greater than zero then the pattern will be applied at most n - 1 times, the array's length will be no greater than n, and...
How can I get the version defined in setup.py (setuptools) in my package?
How could I get the version defined in setup.py from my package (for --version , or other purposes)?
16 Answers
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