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Threads vs Processes in Linux
...ter to use processes instead of threads, since Linux is very efficient in handling processes, and because there are so many problems (such as locking) associated with threads. However, I am suspicious, because it seems like threads could give a pretty big performance gain in some situations.
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How to make a flat list out of list of lists?
...for item in sublist]
As evidence, you can use the timeit module in the standard library:
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' '[item for sublist in l for item in sublist]'
10000 loops, best of 3: 143 usec per loop
$ python -mtimeit -s'l=[[1,2,3],[4,5,6], [7], [8,9]]*99' 'sum(l...
What does the “at” (@) symbol do in Python?
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An @ symbol at the beginning of a line is used for class, function and method decorators.
Read more here:
PEP 318: Decorators
Python Decorators
The most common Python decorators you'll run into are:
@property
@classmethod
@staticmethod
If you see an @ in the middle of a line, that's ...
Browser detection in JavaScript? [duplicate]
How do I determine the exact browser and version using JavaScript?
26 Answers
26
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Capturing Groups From a Grep RegEx
..._[0-9a-z]*"
for f in $files # unquoted in order to allow the glob to expand
do
if [[ $f =~ $regex ]]
then
name="${BASH_REMATCH[1]}"
echo "${name}.jpg" # concatenate strings
name="${name}.jpg" # same thing stored in a variable
else
echo "$f doesn't...
How would you implement an LRU cache in Java?
...ructures would you use? I've already implemented one using LinkedHashMap and Collections#synchronizedMap , but I'm curious if any of the new concurrent collections would be better candidates.
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Resize HTML5 canvas to fit window
...get rid of the scrollbars, add "overflow: hidden" to the style of the html and body elements. See thefutureoftheweb.com/blog/100-percent-height-interface
– Denis Washington
Mar 16 '12 at 7:45
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How do I find the next commit in git? (child/children of ref)
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To list all the commits, starting from the current one, and then its child, and so on - basically standard git log, but going the other way in time, use something like
git log --reverse --ancestry-path 894e8b4e93d8f3^..master
where 894e8b4e93d8f3 is the first commit you want to...
UIImagePickerController error: Snapshotting a view that has not been rendered results in an empty sn
I am getting this error only in iOS 7 and the application crashed.
In iOS 6, I never get any error, just once of memory warning when opening the camera.
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Conversion of a datetime2 data type to a datetime data type results out-of-range value
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I changed my datacolumns and used typeof now... Further I found my problem. there was 1 datarow that contained a wrong date, which triggered the error
– Gerbrand
Aug 26 '09 at 5:46
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