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What's a “static method” in C#?
...) { return 1; }
public static int StaticMethod() { return 42; }
}
In order to call InstanceMethod, you need an instance of the class:
SomeClass instance = new SomeClass();
instance.InstanceMethod(); //Fine
instance.StaticMethod(); //Won't compile
SomeClass.InstanceMethod(); //Won't co...
Update multiple rows in same query using PostgreSQL
... one column, it's much more generalizable:
update test as t set
column_a = c.column_a
from (values
('123', 1),
('345', 2)
) as c(column_b, column_a)
where c.column_b = t.column_b;
You can add as many columns as you like:
update test as t set
column_a = c.column_a,
column_c...
Configure Flask dev server to be visible across the network
...
Add below lines to your project
if __name__ == '__main__':
app.debug = True
app.run(host = '0.0.0.0',port=5005)
share
|
improve this answer
...
Concatenating two one-dimensional NumPy arrays
...There are several possibilities for concatenating 1D arrays, e.g.,
numpy.r_[a, a],
numpy.stack([a, a]).reshape(-1),
numpy.hstack([a, a]),
numpy.concatenate([a, a])
All those options are equally fast for large arrays; for small ones, concatenate has a slight edge:
The plot was created with perf...
What is a C++ delegate?
...ouble d)> f = std::bind(&MyClass::DoStuff, this, std::placeholders::_1);
// auto f = std::bind(...); in C++11
Option 7: templates
Accept anything as long as it matches the argument list.
template <class FunctionT>
int DoSomething(FunctionT func)
{
return func(3.14);
}
...
How to .gitignore files recursively
... the repo root (parent directory of /Webapp).
– lucid_dreamer
May 6 '18 at 22:33
1
...
How do you access the matched groups in a JavaScript regular expression?
...an access capturing groups like this:
var myString = "something format_abc";
var myRegexp = /(?:^|\s)format_(.*?)(?:\s|$)/g;
var match = myRegexp.exec(myString);
console.log(match[1]); // abc
And if there are multiple matches you can iterate over them:
var myString = "something f...
How to write log base(2) in c/c++
...
#define M_LOG2E 1.44269504088896340736 // log2(e)
inline long double log2(const long double x){
return log(x) * M_LOG2E;
}
(multiplication may be faster than division)
...
Swift Programming: getter/setter in stored property
...orarily wrong, you should wrap a computed property around it.
private var _foo:Int = 0
var foo:Int {
get {
return _foo
}
set {
if(newValue > 999) {
_foo = 999
} else {
_foo = newValue
}
}
}
Or:
private var _foo:Int = 0
va...
Android SDK installation doesn't find JDK
... Doesn't work for me on Windows 7 x64. I'm not joking. I set JAVA_HOME and I tried clicking back and next several times, but it's still not working. Neither does running SDK Manager.exe from the archive and I am positive I have JDK 7 installed (even ran the installer again and it told me i...
