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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...
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 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...
Optimal settings for exporting SVGs for the web from Illustrator?
...VG logo for a website — to make it look great on a responsive design for all devices.
2 Answers
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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 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 "...
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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In Windows Azure: What are web role, worker role and VM role?
... to host the application in Windows Azure, so I created a web role. I actually want to know what these roles are for. What is their significance coding wise or storage wise?
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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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