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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 <- ...
Iterate all files in a directory using a 'for' loop
...*) do ( something_here )
In my case I also wanted the file content, name, etc.
This lead to a few issues and I thought my use case might help. Here is a loop that reads info from each '.txt' file in a directory and allows you do do something with it (setx for instance).
@ECHO OFF
setlocal enable...
$location / switching between html5 and hashbang mode / link rewriting
...ass (LocationHashbangUrl, LocationUrl and LocationHashbangInHTML5Url).
In order to simulate URL rewriting you must actually set html5mode to true and decorate the $sniffer class as follows:
$provide.decorator('$sniffer', function($delegate) {
$delegate.history = false;
return $delegate;
});
...
Android Studio doesn't see device
... edit adb_usb.ini, restart computer+device+swap usb port, reinstall studio etc. etc.) I just couldnt get it to work, and could not even detect my device using 'adb devices'. Finally after about 2 hours of googling and testing, someone suggested switching to PTP instead of MTP on my device. When I d...
“You have mail” message in terminal, os X [closed]
... Hitting any key will cause it to continue to display more of the message, etc., until you read the end of it. Or you can scroll with your mouse/touchpad. You may be able to hit q to abort viewing the message (I can't test that just now, but try it).To delete all messages, you'd use command d *. To ...
How to create correct JSONArray in Java using JSONObject
...
@ArnoldBrown In order to add an array to mainObj it has to have a key.
– Grammin
Oct 24 '19 at 22:04
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Why aren't Java Collections remove methods generic?
... and HashSet are checking for the hash code, and TreeSet/Map are using the ordering of the elements. Still, they fully implement Collection.remove, without breaking its contract (if the ordering is consistent to equals). And a varied ArrayList (or AbstractCollection, I think) with the equals call tu...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...(13)-|[UIView:0x85a8fb0]...
This would be trailing horizontal constraint etc.
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How does virtual inheritance solve the “diamond” (multiple inheritance) ambiguity?
...he grandfather!
BUT you still need to specify the methods to be virtual in order to get the methods correctly overrided...
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Having a private branch of a public repo on GitHub?
... Duplication works fine for me, though I had to do it in the opposite order, first creating a private repo and then duplicating the public repo there from the command line. Thanks!
– Joel
Jan 26 '13 at 19:48
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