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Fastest way to get the first object from a queryset in django?
...eturn None if there aren't any. There are lots of ways to do this which all work. But I'm wondering which is the most performant.
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Complete Working Sample of the Gmail Three-Fragment Animation Scenario?
...at I'll refer to as "the Gmail three-fragment animation" scenario. Specifically, we want to start with two fragments, like this:
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Elegant ways to support equivalence (“equality”) in Python classes
When writing custom classes it is often important to allow equivalence by means of the == and != operators. In Python, this is made possible by implementing the __eq__ and __ne__ special methods, respectively. The easiest way I've found to do this is the following method:
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Android: AsyncTask vs Service
...-consuming tasks that cannot be run of the UI thread. A common example is fetching/processing data when a button is pressed.
Services are designed to be continually running in the background. In the example above of fetching data when a button is pressed, you could start a service, let it fetch the...
Determining Referer in PHP
...s the most reliable and secure way to determine what page either sent, or called (via AJAX), the current page. I don't want to use the $_SERVER['HTTP_REFERER'] , because of the (lack of) reliability, and I need the page being called to only come from requests originating on my site.
Edit: I am...
Use numpy array in shared memory for multiprocessing
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To add to @unutbu's (not available anymore) and @Henry Gomersall's answers. You could use shared_arr.get_lock() to synchronize access when needed:
shared_arr = mp.Array(ctypes.c_double, N)
# ...
def f(i): # could be anything numpy accepts as an index such another numpy array
with ...
One-liner to check whether an iterator yields at least one element?
... Similarly if you need to check if the iterator is empty, one could use all(False for _ in iterator) will check if the iterator is empty. (all returns True if the iterator is empty, otherwise it stops when it sees the first False element)
– KGardevoir
Apr 3 ...
What scalability problems have you encountered using a NoSQL data store? [closed]
...ap them to our Java object model, that's with everything correctly indexed etc.
Storing them as key/value pairs using a lightweight text representation: 1 table, 18,000 rows, 3 seconds to retrieve them all and reconstruct the Java objects.
In business terms: first option was not feasible. Second o...
What is cURL in PHP?
...tents() func. Curl enables you to set more options like POST data, cookies etc which file_get_contents() does not provide.
– Dinesh Nagar
Aug 22 '14 at 8:18
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How to sort two lists (which reference each other) in the exact same way
...s problem is to use the "decorate, sort, undecorate" idiom, which is especially simple using python's built-in zip function:
>>> list1 = [3,2,4,1, 1]
>>> list2 = ['three', 'two', 'four', 'one', 'one2']
>>> list1, list2 = zip(*sorted(zip(list1, list2)))
>>> list1
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