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Why is “if not someobj:” better than “if someobj == None:” in Python?
...a __nonzero__ special method (as do numeric built-ins, int and float), it calls this method. It must either return a bool value which is then directly used, or an int value that is considered False if equal to zero.
Otherwise, if the object has a __len__ special method (as do container built-ins, li...
How to decide font color in white or black depending on background color?
... have the intensities for the individual colors, you can determine the overall intensity of the color and choose the corresponding text.
if (red*0.299 + green*0.587 + blue*0.114) > 186 use #000000 else use #ffffff
The threshold of 186 is based on theory, but can be adjusted to taste. Based on ...
Minimizing NExpectation for a custom distribution in Mathematica
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As far as I see, the problem is (as you already wrote), that MeanResidualLife takes a long time to compute, even for a single evaluation. Now, the FindMinimum or similar functions try to find a minimum to the function. Finding a minimum requires either to set the first derivative of the function...
How can I use a C++ library from node.js?
...ows with Visual Studio. See stackoverflow.com/questions/2045774/… for details on how to do this. Or should I be able to use node-ffi on C++ without a wrapper?
– pancake
May 28 '13 at 2:12
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How do I do a not equal in Django queryset filtering?
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Your query appears to have a double negative, you want to exclude all rows where x is not 5, so in other words you want to include all rows where x IS 5. I believe this will do the trick.
results = Model.objects.filter(x=5).exclude(a=true)
To answer your specific question, there is no "...
Can't pickle when using multiprocessing Pool.map()
...nsider it "easy" or not;-) is to add the infrastructure to your program to allow such methods to be pickled, registering it with the copy_reg standard library method.
For example, Steven Bethard's contribution to this thread (towards the end of the thread) shows one perfectly workable approach to a...
How to make an immutable object in Python?
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Can you use namedtuple internally inside the class instead of instantiating the object externally? I'm very new to python but the advantage to your other answer is that I can have a class hide the details and also have the power of things like optional p...
When should iteritems() be used instead of items()?
Is it legitimate to use items() instead of iteritems() in all places? Why was iteritems() removed from Python 3? Seems like a terrific and useful method. What's the reasoning behind it?
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How to join two JavaScript Objects, without using JQUERY [duplicate]
... merge them and crete a single json object.
The resultant json should have all the values from obj2 and the values from obj1 which is not present in obj2.
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Convert base-2 binary number string to int
... (as suggested by the >>> prompt), you don't need to use print at all. The OP's hypothetical example didn't. So it really should be identical in Python 2 and 3.
– John Y
Jul 12 '16 at 22:36
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