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Java: random long number in 0
...ause directly using rng.nextLong() % n will be give uniform values (assume all bits are good). You can ignore that part if you want.
– kennytm
Mar 30 '10 at 20:07
...
Keep only date part when using pandas.to_datetime
...fault represents the dates with datetime64[ns] even though the dates are all daily only.
I wonder whether there is an elegant/clever way to convert the dates to datetime.date or datetime64[D] so that, when I write the data to CSV, the dates are not appended with 00:00:00 . I know I can conver...
How can a Java program get its own process ID?
...There exists no platform-independent way that can be guaranteed to work in all jvm implementations.
ManagementFactory.getRuntimeMXBean().getName() looks like the best (closest) solution, and typically includes the PID. It's short, and probably works in every implementation in wide use.
On linux+wind...
Why did Rails4 drop support for “assets” group in the Gemfile
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Wasn't it also saving memory? Now all gems, even those not needed in "production" (only in precompile), are loaded and thus rails consumes more memory?
– gucki
Sep 12 '13 at 9:35
...
setState vs replaceState in React.js
...ows out the current state, and replaces it with only what you provide. Usually setState is used unless you really need to remove keys for some reason; but setting them to false/null is usually a more explicit tactic.
While it's possible it could change; replaceState currently uses the object passe...
Django gives Bad Request (400) when DEBUG = False
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The ALLOWED_HOSTS list should contain fully qualified host names, not urls. Leave out the port and the protocol. If you are using 127.0.0.1, I would add localhost to the list too:
ALLOWED_HOSTS = ['127.0.0.1', 'localhost']
You...
How to skip over an element in .map()?
...nce it has some cost, you can use the more general .reduce(). You can generally express .map() in terms of .reduce:
someArray.map(function(element) {
return transform(element);
});
can be written as
someArray.reduce(function(result, element) {
result.push(transform(element));
return result;
}...
How do you get the footer to stay at the bottom of a Web page?
...roblem is that I can't get the footer to stay at the bottom of the page in all browsers. It works if the content pushes the footer down, but that's not always the case.
...
Mapping many-to-many association table with extra column(s)
...ou don't put any cascade on your relationships, then you must persist/save all the entities. Although only the owning side of the relationship (here, the UserService side) must be initialized, it's also a good practice to make sure both sides are in coherence.
User user = new User();
Service servi...
What does @synchronized() do as a singleton method in objective C?
...probably isn't multithreaded, and you probably don't need to use it (especially if the singleton itself isn't thread-safe).
Edit: Adding some more information that wasn't in the original answer from 2011.
The @synchronized directive prevents multiple threads from entering any region of code that...