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Singletons vs. Application Context in Android?
...en mentioned as another problem, and since singletons imply "global" (= random) access to shared state, subtle bugs may arise when not properly synchronized in concurrent applications.
I consider it an anti-pattern, it's a bad object-oriented style that essentially amounts to maintaining global sta...
How do write IF ELSE statement in a MySQL query
How do I write an IF ELSE statement in a MySQL query?
5 Answers
5
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Measuring function execution time in R
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Another possible way of doing this would be to use Sys.time():
start.time <- Sys.time()
...Relevent codes...
end.time <- Sys.time()
time.taken <- end.time - start.time
time.taken
Not the most elegant way to do it, compared to the answere...
Get: TypeError: 'dict_values' object does not support indexing when using python 3.2.3 [duplicate]
... dict.keys() and dict.items()) returns a view, rather than a list. See the documentation here. You therefore need to wrap your call to dict.values() in a call to list like so:
v = list(d.values())
{names[i]:v[i] for i in range(len(names))}
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Android: ListView elements with multiple clickable buttons
...t 11:39 there is an excellent example: youtu.be/wDBM6wVEO70?t=11m39s Then do what @znq says...setTag() when the convertView==null and do getTag() in the onClick() method of the button's onClickListener(). Thank you!
– Shehaaz
Jun 1 '13 at 23:32
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A weighted version of random.choice
I needed to write a weighted version of random.choice (each element in the list has a different probability for being selected). This is what I came up with:
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How to do an INNER JOIN on multiple columns
... OH, I know why :) it's supposed to be INNER JOIN not INNER_JOIN... DOH!
– Kiril
Mar 2 '10 at 21:37
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How do I get the opposite (negation) of a Boolean in Python?
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>>> list(map(my_not_function, lst))
[False, True, False, True]
Do not use the bitwise invert operator ~ on booleans
One might be tempted to use the bitwise invert operator ~ or the equivalent operator function operator.inv (or one of the other 3 aliases there). But because bool is a sub...
What's the best way to iterate over two or more containers simultaneously
...ed Sep 25 '13 at 13:19
Konrad RudolphKonrad Rudolph
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Can I target all tags with a single selector?
I'd like to target all h tags on a page. I know you can do it this way...
10 Answers
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