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How do I use boolean variables in Perl?
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@BlueWaldo: you can also use cmp and <=> when comparing and assigning the results of the comparison to a scalar. $var = $var1 cmp $var2; 'cmp' and '<=>' (used for numeric comparisons) returns -1, 0, or 1 if left argument is less than, equal to,...
Class method differences in Python: bound, unbound and static
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In Python, there is a distinction between bound and unbound methods.
Basically, a call to a member function (like method_one), a bound function
a_test.method_one()
is translated to
Test.method_one(a_test)
i.e. a call to an unbound method. Because of that, a call to...
What does this mean: Failure [INSTALL_FAILED_CONTAINER_ERROR]?
I try to deploy my app and sometimes get this error:
14 Answers
14
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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 do I make a single legend for many subplots with matplotlib?
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There is also a nice function get_legend_handles_labels() you can call on the last axis (if you iterate over them) that would collect everything you need from label= arguments:
handles, labels = ax.get_legend_handles_labels()
fig.legend(handles, labels, loc='upper c...
[ :Unexpected operator in shell programming [duplicate]
...et of sh syntax - the /bin/sh executable on your system may provide only standard sh functionality, in which []-style tests are not included.
– Tim
Aug 5 '10 at 1:17
13
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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...
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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Are lists thread-safe?
...t is often suggested to use queues with multiple threads, instead of lists and .pop() . Is this because lists are not thread-safe, or for some other reason?
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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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