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Determine if an object property is ko.observable
...ce) {
if ((instance === null) || (instance === undefined) || (instance.__ko_proto__ === undefined)) return false;
if (instance.__ko_proto__ === ko.dependentObservable) return true;
return ko.isComputed(instance.__ko_proto__); // Walk the prototype chain
};
UPDATE: If you are using KO 2...
Improve INSERT-per-second performance of SQLite
...more memory will be used for your database.
If you have indices, consider calling CREATE INDEX after doing all your inserts. This is significantly faster than creating the index and then doing your inserts.
You have to be quite careful if you have concurrent access to SQLite, as the whole database i...
How to increment a datetime by one day?
...
All of the current answers are wrong in some cases as they do not consider that timezones change their offset relative to UTC. So in some cases adding 24h is different from adding a calendar day.
Proposed solution
The follo...
What is the best way to repeatedly execute a function every x seconds?
...uler.
import sched, time
s = sched.scheduler(time.time, time.sleep)
def do_something(sc):
print("Doing stuff...")
# do your stuff
s.enter(60, 1, do_something, (sc,))
s.enter(60, 1, do_something, (s,))
s.run()
If you're already using an event loop library like asyncio, trio, tkinter,...
How to overcome TypeError: unhashable type: 'list'
...used to compare dictionary keys during a dictionary lookup quickly.
Internally, hash() method calls __hash__() method of an object which are set by default for any object.
Converting a nested list to a set
>>> a = [1,2,3,4,[5,6,7],8,9]
>>> set(a)
Traceback (most recent call last...
What is a stored procedure?
... a couple of ways. Most major DBMs support stored procedures; however, not all do. You will need to verify with your particular DBMS help documentation for specifics. As I am most familiar with SQL Server I will use that as my samples.
To create a stored procedure the syntax is fairly simple:
CRE...
Detect current device with UI_USER_INTERFACE_IDIOM() in Swift
What is the equivalent of UI_USER_INTERFACE_IDIOM() in Swift to detect between iPhone and iPad?
17 Answers
...
When should you use constexpr capability in C++11?
... "function that always returns 5" is breaking or diluting the meaning of "calling a function". There must be a reason, or a need for this capability or it wouldn't be in C++11. Why is it there?
...
Why doesn't GCC optimize a*a*a*a*a*a to (a*a*a)*(a*a*a)?
...scientific application. One thing I noticed is that GCC will optimize the call pow(a,2) by compiling it into a*a , but the call pow(a,6) is not optimized and will actually call the library function pow , which greatly slows down the performance. (In contrast, Intel C++ Compiler , executable ...
Selecting a row of pandas series/dataframe by integer index
... edited Jun 5 '18 at 12:40
marc_aragones
3,37644 gold badges2323 silver badges3333 bronze badges
answered Apr 19 '13 at 12:20
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