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What does iota of std::iota stand for?
...ase Greek letter iota.
In the quote above, I typed ι, U+03B9, “GREEK SMALL LETTER IOTA”, but Unicode actually has a dedicated code point for APL's iota: ⍳ is U+2373, “APL FUNCTIONAL SYMBOL IOTA”.
In response to the demands of commenters, I shall further address the etymology of “iot...
What's the best way to join on the same table twice?
...a fan of natural keys and this is a great example why. Natural keys, especially things like phone numbers, can change and frequently so. Updating your database when that change happens will be a HUGE, error-prone headache. *
Method 1 as you describe it is your best bet though. It looks a bit terse ...
Does the join order matter in SQL?
...ssociative as long as neither predicate can be satisfied by a row in which all columns from one table are NULL, than to say that it's associative as long as the predicates don't involve IS NULL or 'a function that is related to nulls'. One can easily imagine a predicate that satisfies the former des...
How to check if an object is an array?
... {
Array.isArray = function(obj) {
return Object.prototype.toString.call(obj) === '[object Array]';
}
};
If you use jQuery you can use jQuery.isArray(obj) or $.isArray(obj). If you use underscore you can use _.isArray(obj)
If you don't need to detect arrays created in different frames you...
Does Python support multithreading? Can it speed up execution time?
...
The GIL does not prevent threading. All the GIL does is make sure only one thread is executing Python code at a time; control still switches between threads.
What the GIL prevents then, is making use of more than one CPU core or separate CPUs to run threads in...
Add a dependency in Maven
...d you're just trying to add your JAR to your local repository, you can install it as follows, using any arbitrary groupId/artifactIds:
mvn install:install-file -DgroupId=com.stackoverflow... -DartifactId=yourartifactid... -Dversion=1.0 -Dpackaging=jar -Dfile=/path/to/jarfile
You can also deploy it ...
Most efficient way of making an if-elif-elif-else statement when the else is done the most?
...doThisMostOfTheTime)()
...looks like it ought to be faster, but it's actually slower than the if ... elif ... else construct, because it has to call a function, which can be a significant performance overhead in a tight loop.
Consider these examples...
1.py
something = 'something'
for i in xra...
Explanation of JSONB introduced by PostgreSQL
...
First, hstore is a contrib module, which only allows you to store key => value pairs, where keys and values can only be texts (however values can be sql NULLs too).
Both json & jsonb allows you to store a valid JSON value (defined in its spec).
F.ex. these are v...
WPF Application that only has a tray icon
... an application that starts minimized to tray. The idea is that it periodically fetches an RSS Feed and creates a Toaster-Popup when there are new feeds.
...
How to execute multi-line statements within Python's own debugger (PDB)
So I am running a Python script within which I am calling Python's debugger, PDB by writing:
6 Answers
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