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Summarizing multiple columns with dplyr? [duplicate]
...
The dplyr package contains summarise_all for this aim:
library(dplyr)
df %>% group_by(grp) %>% summarise_all(list(mean))
#> # A tibble: 3 x 5
#> grp a b c d
#> <int> <dbl> <dbl> <dbl> <dbl>
#>...
How can I list ALL DNS records?
... specific nameserver: dig -x example.com
#!/bin/bash
set -e; set -u
COMMON_SUBDOMAINS="www mail mx a.mx smtp pop imap blog en ftp ssh login"
EXTENDED=""
while :; do case "$1" in
--) shift; break ;;
-x) EXTENDED=y; shift ;;
-s) NS="$2"; shift 2 ;;
*) break ;;
esac; done
DOM="$1"; shift
TYPE...
How do you overcome the HTML form nesting limitation?
...ete correspond to different actions on the resource: "Save" -> POST /my_resource (creating a new resource) "Save" -> PUT /my_resource (modifying an existing resource) "Delete" -> DELETE /my_resource (destroy the resource) RESTfully speaking, the problem is that a POST is expected to...
Understanding MongoDB BSON Document size limit
... including the subdocuments, nested objects etc.
So a document of:
{
_id:{},
na: [1,2,3],
naa: [
{w:1,v:2,b:[1,2,3]},
{w:5,b:2,h:[{d:5,g:7},{}]}
]
}
Has a maximum size of 16meg.
Sbudocuments and nested objects are all counted towards the size of the document.
...
Changing the status bar text color in splash screen iOS 7
..., UIApplicationDelegate {
var window: UIWindow?
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplicationLaunchOptionsKey: Any]?) -> Bool {
UIApplication.shared.statusBarView?.backgroundColor = UIColor.red
return true
...
What are the most-used vim commands/keypresses?
...dows
^Wn new window
^Wj down to next window; ^Wk up to previous window
^W_ maximise current window; ^W= make all windows equal size
^W+ increase window size; ^W- decrease window size
Source Navigation
% jump to matching parenthesis/bracket/brace, or language block if language module loaded
gd ...
Error - trustAnchors parameter must be non-empty
...net.debug=all -Djavax.net.ssl.trustStore=/Another/path/to/cacerts -jar test_get_https-0.0.1-SNAPSHOT-jar-with-dependencies.jar https://www.calca.com.py 2>&1| grep -i truststore
share
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impr...
Get/pick an image from Android's built-in Gallery app programmatically
...ing at the response from our own action
private static final int SELECT_PICTURE = 1;
private String selectedImagePath;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
findViewById(R.id.Button0...
Left-pad printf with spaces
...ructure). The indent is the number of spaces before the string.
void print_with_indent(int indent, char * string)
{
printf("%*s%s", indent, "", string);
}
share
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improve this answer
...
Naming convention for Scala constants?
...ER!!!")
case Some(lowerConst) => println("lower!")
case _ => println("mismatch!")
}
}
}
}
Naively I would have expected that to reach all of the cases in the match. Instead it prints:
Input 'Some(lower)' results in: lower!
Input 'Some(UPPER)' results in: UPPER!!...