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Executing periodic actions in Python [duplicate]
...
At the end of foo(), create a Timer which calls foo() itself after 10 seconds.
Because, Timer create a new thread to call foo().
You can do other stuff without being blocked.
import time, threading
def foo():
print(time.ctime())
threading.Timer(10, foo).sta...
Sass .scss: Nesting and multiple classes?
..., so the following is possible too:
.container {
background:red;
#id &{
background:blue;
}
}
/* compiles to: */
.container {
background: red;
}
#id .container {
background: blue;
}
However be aware, that this somehow breaks your nesting structure and thus may incre...
Why does calling a method in my derived class call the base class method?
...howInfo()
{
Console.WriteLine("I am a student!");
}
}
If called, the behavior of ShowInfo varies, based on the implementation:
Person person = new Teacher();
person.ShowInfo(); // Shows 'I am a teacher!'
person = new Student();
person.ShowInfo(); // Shows 'I am a student!'
...
How do I escape reserved words used as column names? MySQL/Create Table
...f ANSI SQL mode is enabled
CREATE TABLE IF NOT EXISTS misc_info
(
id INTEGER PRIMARY KEY AUTO_INCREMENT NOT NULL,
"key" TEXT UNIQUE NOT NULL,
value TEXT NOT NULL
)
ENGINE=INNODB;
or the proprietary back tick escaping otherwise. (Where to find the ` character on various key...
Is recursion ever faster than looping?
...ich transforms certain types of recursion (actually, certain types of tail calls) into jumps instead of function calls.
In functional programming language implementations, sometimes, iteration can be very expensive and recursion can be very cheap. In many, recursion is transformed into a simple ju...
How to vertically center a inside a div? [duplicate]
...ugh therein references a third option: display:table-cell; vertical-align:middle (along with a display:table-row parent). :) But no, you can be sure that I would never advocate using HTML table elements for layout.
– Phrogz
Dec 5 '10 at 4:19
...
Sankey Diagrams in R?
...ms. Here you can find an example. I also added a screenshot so you have an idea what it looks like.
# Load package
library(networkD3)
# Load energy projection data
# Load energy projection data
URL <- paste0(
"https://cdn.rawgit.com/christophergandrud/networkD3/",
"master/JSONda...
Get index of selected option with jQuery
...
@Guffa Any idea as to why the selectedIndex doesn't start from 0 with the first option?
– adamj
Mar 25 '16 at 23:27
...
How to force garbage collector to run?
...oing it more than necessary is inadvisable. The code for when it should be called is well written. You should normally only self collect in specialized edge cases. stackoverflow.com/a/21961777/2710988
– Brandon Barkley
Mar 7 '19 at 19:13
...
Canary release strategy vs. Blue/Green
...r not the new 'green' version is exposed to real users. If it is, then I'd call it Canary. A common way to implement Canary is regular Blue/Green with the addition of smart routing of specific users to the new version. Read the post for a detailed comparison
Blue/Green:
Canary:
...