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Django South - table already exists

...ing database and app you can use the south conversion command ./manage.py convert_to_south myapp This has to be applied before you do any changes to what is already in the database. The convert_to_south command only works entirely on the first machine you run it on. Once you’ve committed the ...
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How do you obtain a Drawable object from a resource id in android package?

...way to use the code below (or something like it) to get an object from the android.R.drawable.* package? 6 Answers ...
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Difference between encoding and encryption

... want to store text on a hard drive, you're going to have to find a way to convert your characters to bits. Alternatively, if all you have is a flash light, you might want to encode your text using Morse. The result is always "readable", provided you know how it's stored. Encryption means you want ...
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Safe (bounds-checked) array lookup in Swift, through optional bindings?

If I have an array in Swift, and try to access an index that is out of bounds, there is an unsurprising runtime error: 19 A...
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Implements vs extends: When to use? What's the difference?

Please explain in an easy to understand language or a link to some article. 18 Answers ...
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How do I calculate percentiles with python/numpy?

...ed in the SciPy Stats package. It has the percentile function you're after and many other statistical goodies. percentile() is available in numpy too. import numpy as np a = np.array([1,2,3,4,5]) p = np.percentile(a, 50) # return 50th percentile, e.g median. print p 3.0 This ticket leads me to b...
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How to use the C socket API in C++ on z/OS

... Keep a copy of the IBM manuals handy: z/OS V1R11.0 XL C/C++ Programming Guide z/OS V1R11.0 XL C/C++ Run-Time Library Reference The IBM publications are generally very good, but you need to get used to their format, as well as knowing where to look...
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Why does this loop produce “warning: iteration 3u invokes undefined behavior” and output more than 4

...s no such thing as "unsigned integer overflow") means undefined behaviour. And this means anything can happen, and discussing why does it happen under the rules of C++ doesn't make sense. C++11 draft N3337: §5.4:1 If during the evaluation of an expression, the result is not mathematically de...
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Maximum number of threads in a .NET app?

What is the maximum number of threads you can create in a C# application? And what happens when you reach this limit? Is an exception of some kind thrown? ...
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How to check that an object is empty in PHP?

... all } If SimpleXMLElement is more than one level deep, you can start by converting it to a pure array: $obj = simplexml_load_file($url); // `json_decode(json_encode($obj), TRUE)` can be slow because // you're converting to and from a JSON string. // I don't know another simple way to do a deep c...