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Check if a given key already exists in a dictionary and increment it
...ording to his example, it should be enough to set "defaultdict(lambda: 0)" and skip the entire "if" clause.
– Deestan
Jan 23 '09 at 14:57
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Default text which won't be shown in drop-down list
...orked perfectly fine for me so I made my research in order to avoid any Js and CSS, but just sticking with HTML.
Adding a value of selected to the item we want to appear as a header forces it to show in the first place as a placeholder.
Something like:
<option selected disabled>Choose here&l...
What is the coolest thing you can do in
...hing you can do in a few lines of simple code. I'm sure you can write a Mandelbrot set in Haskell in 15 lines but it's difficult to follow.
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What is the difference between __init__ and __call__?
I want to know the difference between __init__ and __call__ methods.
13 Answers
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Parsing command-line arguments in C?
... by word, or character by character in C. It has to be able to read in command line options -l -w -i or -- ...
12 Answers
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Are 2^n and n*2^n in the same time complexity?
... answer this question.
The definition is that f(x) belongs to O(g(x)) if and only if the limit limsupx → ∞ (f(x)/g(x)) exists i.e. is not infinity. In short this means that there exists a constant M, such that value of f(x)/g(x) is never greater than M.
In the case of your question let f(n) ...
Python function attributes - uses and abuses [closed]
Not many are aware of this feature, but Python's functions (and methods) can have attributes . Behold:
8 Answers
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Python subprocess.Popen “OSError: [Errno 12] Cannot allocate memory”
...msize of the process that failed to fork, at the time of the fork attempt, and then compare to the amount of free memory (physical and swap) as it relates to the overcommit policy (plug the numbers in.)
In your particular case, note that Virtuozzo has additional checks in overcommit enforcement. M...
CRON job to run on the last day of the month
...ed to find another way.
However, it's usually both substantially easier and correct to run the job as soon as possible on the first day of each month, with something like:
0 0 1 * * myjob.sh
and modify the script to process the previous month's data.
This removes any hassles you may encounter...
Django dynamic model fields
... their own data fields (via the admin) to collect additional data in forms and report on the data. The latter bit makes JSONField not a great option, so instead I have the following solution:
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