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Safest way to convert float to integer in python?
...e more, the number is padded with zeroes on the right.
It follows that 53 ones is the largest number that can be stored without padding. Naturally, all (integer) numbers requiring less digits can be stored accurately.
Adding one to 111(omitted)111 (53 ones) yields 100...000, (53 zeroes). As we kno...
Run cron job only if it isn't already running
...ck your own processes ("ps -u $(whoami) -opid=") and see if you're running one with the same PID ("grep -P "^\s*$(cat ${PIDFILE})$""). If you're not, then it will start the program as before, overwrite the PID file with the new PID, and exit. I see no reason to modify the script; do you?
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What does the 'static' keyword do in a class?
...rs belong to the class instead of a specific instance.
It means that only one instance of a static field exists[1] even if you create a million instances of the class or you don't create any. It will be shared by all instances.
Since static methods also do not belong to a specific instance, they c...
What is the order of precedence for CSS?
I'm trying to figure out why one of my css classes seems to override the other (and not the other way around)
8 Answers
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Does SQLAlchemy have an equivalent of Django's get_or_create?
...could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).first()
if instance:
return instance, False
else:
params = dict((k, v) for k, v in kwargs.iteritems() if not isinstance(v, Clause...
Why is “throws Exception” necessary when calling a function?
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In Java, as you may know, exceptions can be categorized into two: One that needs the throws clause or must be handled if you don't specify one and another one that doesn't. Now, see the following figure:
In Java, you can throw anything that extends the Throwable class. However, you don't...
Text editor to open big (giant, huge, large) text files [closed]
...or tail." It's really a log file analyzer, not a large file viewer, and in one test it required 10 seconds and 700 MB of RAM to load a 250 MB file. But its killer features are the columnizer (parse logs that are in CSV, JSONL, etc. and display in a spreadsheet format) and the highlighter (show lines...
How do I find the next commit in git? (child/children of ref)
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To list all the commits, starting from the current one, and then its child, and so on - basically standard git log, but going the other way in time, use something like
git log --reverse --ancestry-path 894e8b4e93d8f3^..master
where 894e8b4e93d8f3 is the first commit you wa...
What are the differences between utf8_general_ci and utf8_unicode_ci? [duplicate]
...general_ci is a very simple — and on Unicode, very broken — collation, one that gives incorrect results on general Unicode text. What it does is:
converts to Unicode normalization form D for canonical decomposition
removes any combining characters
converts to upper case
This does not wo...
event.preventDefault() vs. return false
...er event handlers from executing after a certain event is fired, I can use one of two techniques. I'll use jQuery in the examples, but this applies to plain-JS as well:
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