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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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Asynchronous shell exec in PHP
...verted to use echo "sudo command" | at now and commenting www-data out in /etc/at.deny
– Julien
Apr 16 '15 at 7:47
@Ju...
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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How do I choose between Tesseract and OpenCV? [closed]
... image inputs (a single word, line, paragraph, page, limited dictionaries, etc.).
OpenCV, on the other hand, is a computer vision library that includes features that let you perform some feature extraction and data classification. You can create a simple letter segmenter and classifier that performs...