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Java: when to use static methods
...e purpose of a car object is to allow instantiation of cars, not provide a comparison between them. Those should be external to the class.
– Zack Jannsen
Aug 13 '12 at 11:04
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What is the difference between NULL, '\0' and 0?
...he value 0, it is just described in different ways.
If a pointer is being compared to the constant literal 0, then this is a check to see if the pointer is a null pointer. This 0 is then referred to as a null pointer constant. The C standard defines that 0 cast to the type void * is both a null poi...
Get the generated SQL statement from a SqlCommand object?
...using "execute stored procedure" in SSMS. We mostly used SPs so the "text" command doesn't account for parameters etc
public static String ParameterValueForSQL(this SqlParameter sp)
{
String retval = "";
switch (sp.SqlDbType)
{
case SqlDbType.Char:
...
JPA : How to convert a native query result set to POJO class collection
...class was not a known Entity. I ended up using this approach stackoverflow.com/questions/5024533/… instead of trying to use a native query.
– FGreg
Jan 30 '13 at 21:43
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Why isn't Python very good for functional programming? [closed]
...ne of the prettiest languages I know. When I write functional Python, it becomes as ugly and unpleasant as your average language that doesn't have a BDFL.
Which is not to say that it's bad, just that you have to work harder than you would if you switched to a language that promotes functional progr...
What are the best use cases for Akka framework [closed]
... scala by the way)
One of the big advantages is the ease at which you can compose a system out of actors and messages with almost no boilerplating, it scales extremely well without all the complexities of hand-rolled threading and you get asynchronous message passing between objects almost for free...
How to prevent buttons from submitting forms
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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
I...
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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