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Is an index needed for a primary key in SQLite?
...d with a specific rowid, or for all records with rowids within a specified range is around twice as fast as a similar search made by specifying any other PRIMARY KEY or indexed value.
With one exception noted below, if a rowid table has a primary key that consists of a single column and the declared...
Difference between .tagName and .nodeName
...most practical purposes stick to nodeName due to its support
for a wider range of scenarios and potentially better forward
compatibility. Not to mention that it doesn’t hiccup on a comment
node, which has a tendency to creep into code unannounced. Don’t worry
about IE 5.5 or Konqueror as...
Is it safe to use -1 to set all bits to true?
... happens is that it repeatedly adds one more than ULONG_MAX until it is in range (6.3.1.3 in the C TC2 draft). In C++ it's the same, just using another way formalizing it (modulo 2^n). It all comes down to mathematical relations.
– Johannes Schaub - litb
Apr 30...
What happens to a detached thread when main() exits?
... Since every thread has its own stack (which is in the megabytes range on Linux), I would choose to detach the thread (so its stack will be freed as soon as it exits) and use some sync primitives if the main thread needs to exit (and for proper shutdown it needs to join the still running t...
Scatter plot and Color mapping in Python
I have a range of points x and y stored in numpy arrays.
Those represent x(t) and y(t) where t=0...T-1
3 Answers
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How should I log while using multiprocessing in Python?
... = multiprocessing.Pool(4, worker_init, [q])
for result in pool.map(f, range(10)):
pass
pool.close()
pool.join()
q_listener.stop()
if __name__ == '__main__':
main()
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Best way to store date/time in mongodb
...: ISODate("2014-02-10T10:50:57.240Z") }
The native type supports a whole range of useful methods out of the box, which you can use in your map-reduce jobs, for example.
If you need to, you can easily convert Date objects to and from Unix timestamps1), using the getTime() method and Date(milliseco...
Bower and devDependencies vs dependencies
...ge URL, physical location or registry name
- <target> is a valid range, commit, branch, etc.
- <name> is the name it should have locally.
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Filtering a list based on a list of booleans
...
filtered_list = [list_a[i] for i in range(len(list_a)) if filter[i]]
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Get the closest number out of an array
...his in action:
def closest (num, arr):
curr = arr[0]
for index in range (len (arr)):
if abs (num - arr[index]) < abs (num - curr):
curr = arr[index]
return curr
array = [2, 42, 82, 122, 162, 202, 242, 282, 322, 362]
number = 112
print closest (number, array)
...