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Order data frame rows according to vector with specific order
...
I prefer to use ***_join in dplyr whenever I need to match data. One possible try for this
left_join(data.frame(name=target),df,by="name")
Note that the input for ***_join require tbls or data.frame
...
Call a Javascript function every 5 seconds continuously [duplicate]
...until the previous function call has finished.
– gion_13
Nov 16 '15 at 7:10
1
How do we break out...
How to install latest version of git on CentOS 7.x/6.x
... repo package:
yum install http://opensource.wandisco.com/centos/6/git/x86_64/wandisco-git-release-6-1.noarch.rpm
- or -
yum install http://opensource.wandisco.com/centos/7/git/x86_64/wandisco-git-release-7-1.noarch.rpm
- or -
yum install http://opensource.wandisco.com/centos/7/git/x86_64/wandisco-...
What is the difference between “def” and “val” to define a function
...ion every time (new instance of Function1).
def even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = false
val even: Int => Boolean = _ % 2 == 0
even eq even
//Boolean = true
With def you can get new function on every call:
val test: () => Int = {
val r = util.Random.nextInt
...
When would you use delegates in C#? [closed]
...e delegate's invocation.
public class DataProvider
{
protected string _connectionString;
public DataProvider( string psConnectionString )
{
_connectionString = psConnectionString;
}
public void UseReader( string psSELECT, DataReaderUser readerUser )
{
using...
Why no generics in Go?
...to its concrete type. Get the gritty details here: golang.org/ref/spec#Type_assertions
– tbone
Aug 25 '13 at 20:50
...
In log4j, does checking isDebugEnabled before logging improve performance?
... running at log level of INFO or ERROR
– AztecWarrior_25
Mar 10 '18 at 0:51
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PHP code to convert a MySQL query to CSV [closed]
...RMINATED BY ',' OPTIONALLY ENCLOSED BY '"'
LINES TERMINATED BY "\n"
FROM my_table;
(the documentation for this is here: http://dev.mysql.com/doc/refman/5.0/en/select.html)
or:
$select = "SELECT * FROM table_name";
$export = mysql_query ( $select ) or die ( "Sql error : " . mysql_error( ) );
$f...
NSRange to Range
...nd 2, so depending on which Swift you're using:
Swift 3.0
func textField(_ textField: UITextField,
shouldChangeCharactersIn range: NSRange,
replacementString string: String) -> Bool {
let nsString = textField.text as NSString?
let newString = nsString?.replaci...
what is reverse() in Django
...t's suppose that in your urls.py you have defined this:
url(r'^foo$', some_view, name='url_name'),
In a template you can then refer to this url as:
<!-- django <= 1.4 -->
<a href="{% url url_name %}">link which calls some_view</a>
<!-- django >= 1.5 or with {% load ur...