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Why should I capitalize my SQL keywords? [duplicate]
...ors. This said, while this convention is a good thing for DML/DDL such as SELECT/INSERT queries and such, it can make for heavy look of Procedural extensions to SQL as in stored procs.
– mjv
Dec 9 '09 at 4:34
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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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Principal component analysis in Python
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Months later, here's a small class PCA, and a picture:
#!/usr/bin/env python
""" a small class for Principal Component Analysis
Usage:
p = PCA( A, fraction=0.90 )
In:
A: an array of e.g. 1000 observations x 20 variables, 1000 rows x 20 colum...
How to determine if Javascript array contains an object with an attribute that equals a given value?
...lt;0 || splice(index, 1) here is my a bit updated code: const index = this.selected.indexOf(this.selected.find(s => s.id == passedObj.id))
– Leonid Zadorozhnykh
Aug 24 '17 at 8:27
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Exporting functions from a DLL with dllexport
...ain C exports, use a C project not C++. C++ DLLs rely on name-mangling for all the C++isms (namespaces etc...). You can compile your code as C by going into your project settings under C/C++->Advanced, there is an option "Compile As" which corresponds to the compiler switches /TP and /TC.
If you ...
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 ...
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...
Django: How to completely uninstall a Django app?
What is the procedure for completely uninstalling a Django app, complete with database removal?
5 Answers
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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 ...
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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