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Rank function in MySQL
...ption is to use a ranking variable, such as the following:
SELECT first_name,
age,
gender,
@curRank := @curRank + 1 AS rank
FROM person p, (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requi...
What is the difference between Python's list methods append and extend?
...ppend
The list.append method appends an object to the end of the list.
my_list.append(object)
Whatever the object is, whether a number, a string, another list, or something else, it gets added onto the end of my_list as a single entry on the list.
>>> my_list
['foo', 'bar']
>>&...
How do I PHP-unserialize a jQuery-serialized form?
...ou are using a POST ajax request. So in PHP, you would access values like $_POST["varname"] or $_GET["varname"] depending on the request type.
The serialize method just takes the form elements and puts them in string form. "varname=val&var2=val2"
...
How to get Scala List from Java List?
...now built into the language using:
import scala.collection.JavaConversions._
...
lst.toList.foreach{ node => .... }
works. asScala did not work
In 2.12.x use import scala.collection.JavaConverters._
In 2.13.x use import scala.jdk.CollectionConverters._
...
receiver type *** for instance message is a forward declaration
...wered Jan 11 '12 at 6:47
Catfish_ManCatfish_Man
38.6k1111 gold badges6363 silver badges8181 bronze badges
...
C++ convert hex string to signed integer
...>> x;
// output it as a signed type
std::cout << static_cast<int>(x) << std::endl;
}
In the new C++11 standard, there are a few new utility functions which you can make use of! specifically, there is a family of "string to number" functions (http://en.cppreference.c...
Automatic vertical scroll bar in WPF TextBlock?
...del : ILogBoxViewModel, INotifyPropertyChanged
{
private readonly ILog _log = LogManager.GetLogger<LogBoxViewModel>();
private bool _attachedPropertyClear;
private string _attachedPropertyAppend;
public void CmdAppend(string toAppend)
{
string toLog = $"{DateTime....
How to access component methods from “outside” in ReactJS?
...
class Parent extends React.Class {
constructor(props) {
this._child = React.createRef();
}
componentDidMount() {
console.log(this._child.current.someMethod()); // Prints 'bar'
}
render() {
return (
<div>
<Child ref=...
What's the scope of a variable initialized in an if statement?
...ked only at runtime -- that is, when you get to the print x statement. If __name__ didn't equal "__main__" then you would get an exception: NameError: name 'x' is not defined.
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Scala best way of turning a Collection into a Map-by-key?
...Traversable[V].mapBy( V => K) were better!
– oxbow_lakes
Jul 14 '10 at 21:17
7
Be aware that t...