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When are C++ macros beneficial? [closed]
...for debug functions, to automatically pass things like __FILE__, __LINE__, etc:
#ifdef ( DEBUG )
#define M_DebugLog( msg ) std::cout << __FILE__ << ":" << __LINE__ << ": " << msg
#else
#define M_DebugLog( msg )
#endif
...
What's the equivalent of use-commit-times for git?
... simple --with-timestamps option for git checkout and friends (clone, pull etc), at the user's discretion.
Both Bazaar and Mercurial stores metadata. Users can apply them or not when checking out. But in git, since original timestamps are not even available in the repo, there is no such option.
So...
Pass a data.frame column name to a function
...1(df, "B")
fun1(df, c("B","A"))
There's no need to use substitute, eval, etc.
You can even pass the desired function as a parameter:
fun1 <- function(x, column, fn) {
fn(x[,column])
}
fun1(df, "B", max)
Alternatively, using [[ also works for selecting a single column at a time:
df <- ...
Closing Database Connections in Java
...method in order to release any other database resources (cursors, handles, etc) the connection may be holding on to.
Actually, the safe pattern in Java is to close your ResultSet, Statement, and Connection (in that order) in a finally block when you are done with them, something like that:
Connec...
Execute code when Django starts ONCE only?
...but that is because runserver has some tricks to validate the models first etc ... normal deployments or even when runserver auto reloads, this is only executed once.
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How to get disk capacity and free space of remote computer
...ay 1 '15 at 17:48
Null Pointers etc.Null Pointers etc.
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Which websocket library to use with Node.js? [closed]
...; TCP connections and provides data-sync, pub/sub and request/response
socketcluster WebSocket server cluster which makes use of all CPU cores on your machine. For example, if you were to use an xlarge Amazon EC2 instance with 32 cores, you would be able to handle almost 32 times the traffic on a si...
How to set time delay in javascript
...
Place your code inside of the { }
500 = 0.5 seconds
2200 = 2.2 seconds
etc.
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How to implement an android:background that doesn't stretch?
...tton instead of ImageButton (which doesn't allow SetText() , resizing, etc.).
11 Answers
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What is the actual use of Class.forName(“oracle.jdbc.driver.OracleDriver”) while connecting to a dat
...uto-load the driver class. So why do we have to manually do Class.forName("etc.driver") ?
– Pacerier
Aug 28 '14 at 22:52
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