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How to prevent buttons from submitting forms
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610
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Does Java have something like C#'s ref and out keywords?
...t's always clear when you're passing something by reference. yoda.arachsys.com/csharp/parameters.html
– Mark Byers
May 10 '10 at 22:03
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Fastest way to replace NAs in a large data.table
...d at NAToUnknown).
EDIT (more elegant solution as requested by Ramnath in comments) :
f_dowle2 = function(DT) {
for (i in names(DT))
DT[is.na(get(i)), (i):=0]
}
system.time(f_dowle2(dt1))
user system elapsed
6.468 0.760 7.250 # faster, too
identical(a_gdata, dt1)
[1] TRUE
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Can enums be subclassed to add new elements?
...have a base class called e.g. IntEnum, that looks like this: stackoverflow.com/questions/1681976/enum-with-int-value-in-java/…. Then all my enums could extend it...in this case just benefitting from inheritance and thus I wouldn't have to duplicate this "int-based enum" code frequently. I am new...
Python subprocess.Popen “OSError: [Errno 12] Cannot allocate memory”
...or because security_vm_enough_memory_mm failed you while enforcing the overcommit policy.
Start by checking the vmsize 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 ...
Alarm 闹钟扩展 · App Inventor 2 中文网
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尽管Android文档强烈建议使用通知（参见 developer.android.com），但在某些情况下，仍然需要在特定时间启动应用程序。使用此扩展，可以在指定时间启动应用程序。如果您想定时生成通知，必须使用扩展 UrsAI2Notifier。
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iOS 6 apps - how to deal with iPhone 5 screen size? [duplicate]
...raints to lay things out. Nothing will be hard-coded, and your life will become a lot simpler.
However, if you have to support older iOS's, then it really depends on your application. A majority of applications that use a standard navigation bar, and/or tab bar, could simply expand the content in t...
Using npm behind corporate proxy .pac
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Bulk insert with SQLAlchemy ORM
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User(name="u2"),
User(name="u3")
]
s.bulk_save_objects(objects)
s.commit()
Here, a bulk insert will be made.
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When to use AtomicReference in Java?
...newValue = someFunctionOfOld(cachedValueToUpdate);
boolean success = cache.compareAndSet(cachedValue,cachedValueToUpdate);
Because of the atomic reference semantics, you can do this even if the cache object is shared amongst threads, without using synchronized. In general, you're better off using ...