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Asynchronous method call in Python?
...multiprocessing module added in Python 2.6. You can use pools of processes and then get results asynchronously with:
apply_async(func[, args[, kwds[, callback]]])
E.g.:
from multiprocessing import Pool
def f(x):
return x*x
if __name__ == '__main__':
pool = Pool(processes=1) ...
What does “not run” mean in R help pages?
...isible on help pages, but will
be run both by the package checking tools, and the
'example()' function. This was previously 'testonly', and
that form is still accepted.
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What is the easiest way to duplicate an activerecord record?
... Does this still work in Rails 3.1.0.beta? When I do q = p.clone, and then p == q, I get true back. On the other hand, if I use q = p.dup, I get false back when comparing them.
– Juno Woods
Feb 8 '11 at 2:10
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You can't specify target table for update in FROM clause
...you should only be selecting the columns you need in that innermost query, and adding a good WHERE clause to limit the results, too.
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What is “entropy and information gain”?
I am reading this book ( NLTK ) and it is confusing. Entropy is defined as :
7 Answers
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What does an exclamation mark mean in the Swift language?
...ome/None), not the value itself (T). So john isn't an instance of Person, and it doesn't have an apartment member:
john.apartment
// 'Person?' does not have a member named 'apartment'
The actual Person value can be unwrapped in various ways:
"forced unwrapping": john! (gives the Person value i...
What exactly is a reentrant function?
...rant?
No.
For example, let's have a C++ function that takes both a lock, and a callback as a parameter:
#include <mutex>
typedef void (*callback)();
std::mutex m;
void foo(callback f)
{
m.lock();
// use the resource protected by the mutex
if (f) {
f();
}
// u...
Where'd padding go, when setting background Drawable?
I have this issue on my EditText and Button views, where I have a nice padding for them to space away from the text, but when I change the background with setBackgroundDrawable or setBackgroundResource that padding is lost forever.
...
How to strip HTML tags from string in JavaScript? [duplicate]
...gt; or <html> or <head> tags is not valid within a <div> and may therefore not be parsed correctly.
textContent (the DOM standard property) and innerText (non-standard) properties are not identical. For example, textContent will include text within a <script> element while in...
WPF - How to force a Command to re-evaluate 'CanExecute' via its CommandBindings
I have a Menu where each MenuItem in the hierarchy has its Command property set to a RoutedCommand I've defined. The associated CommandBinding provides a callback for the evaluation of CanExecute which controls the enabled state of each MenuItem .
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