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Calculate difference in keys contained in two Python dictionaries
...s:
diff = set(dictb.keys()) - set(dicta.keys())
Here is a class to find all the possibilities: what was added, what was removed, which key-value pairs are the same, and which key-value pairs are changed.
class DictDiffer(object):
"""
Calculate the difference between two dictionaries as:
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Why does changing 0.1f to 0 slow down performance by 10x?
...ond run the numbers are very close to zero.
Denormalized numbers are generally rare and thus most processors don't try to handle them efficiently.
To demonstrate that this has everything to do with denormalized numbers, if we flush denormals to zero by adding this to the start of the code:
_MM_...
Calling parent class __init__ with multiple inheritance, what's the right way?
...ing super() leads to greater flexibility for subclasses.
In the direct call approach, C.__init__ can call both A.__init__ and B.__init__.
When using super(), the classes need to be designed for cooperative multiple inheritance where C calls super, which invokes A's code which will also call supe...
Preloading images with JavaScript
Is the function I wrote below enough to preload images in most, if not all, browsers commonly used today?
14 Answers
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Escaping regex string
...this:
4.2.3 re Module Contents
escape(string)
Return string with all non-alphanumerics backslashed; this is useful if you want to match an arbitrary literal string that may have regular expression metacharacters in it.
A simplistic example, search any occurence of the provided string opt...
How do you get the list of targets in a makefile?
...ed rake a bit (a Ruby make program), and it has an option to get a list of all the available targets, eg
20 Answers
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Download the Android SDK components for offline install
Is it possible to download the Android SDK components for offline install without using the SDK Manager?
The problem is I am behind a firewall which I have no control over and both sites download URLs seem to be blocked (throws a connection refused exception)
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Get $_POST from multiple checkboxes
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Set the name in the form to check_list[] and you will be able to access all the checkboxes as an array($_POST['check_list'][]).
Here's a little sample as requested:
<form action="test.php" method="post">
<input type="checkbox" name="check_list[]" value="value 1">
<input t...
ViewPager and fragments — what's the right way to store fragment's state?
...agment will be placed. FragmentPagerAdapter.getItem(int position) is only called when a fragment for that position does not exist. After rotating, Android will notice that it already created/saved a fragment for this particular position and so it simply tries to reconnect with it with FragmentManage...
Symfony 2 EntityManager injection in service
...to inject doctrine EntityManager, but I don't see that __construct() is called on my service, and injection doesn't work.
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