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Update R using RStudio
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You install a new version of R from the official website.
RStudio should automatically start with the new version when you relaunch it.
In case you need to do it manually, in RStudio, go to :Tools -> options -> General.
Chec...
How many bytes does one Unicode character take?
...ing, it defines codepoints and a codepoint is a number, associated with usually a character. I say usually because there are concepts like combining characters. You may be familiar with things like accents, or umlauts. Those can be used with another character, such as an a or a u to create a new log...
How to install Hibernate Tools in Eclipse?
What is the proper way to install Hibernate Tools in Eclipse as a plugin?
The Hibernate site doesn't really give any instructions.
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Why does Apple recommend to use dispatch_once for implementing the singleton pattern under ARC?
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dispatch_once() is absolutely synchronous. Not all GCD methods do things asynchronously (case in point, dispatch_sync() is synchronous). The use of dispatch_once() replaces the following idiom:
+ (MyClass *)sharedInstance {
static MyClass *sharedInstance;
@synchr...
Can one AngularJS controller call another?
...omeDataService)
{
// use the data service, bind to template...
// or call methods on someDataService to send a request to server
}
function SecondController(someDataService)
{
// has a reference to the same instance of the service
// so if the service updates state for example, this contr...
Elements order in a “for (… in …)” loop
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Quoting John Resig:
Currently all major browsers loop over the properties of an object in the order in
which they were defined. Chrome does this as well, except for a couple cases. [...]
This behavior is explicitly left undefined by the ECMAScript specifi...
Removing Java 8 JDK from Mac
So I installed the beta of JDK 8 a while ago to look at some of the examples. I thought for sure by now, it's easy to change between versions.
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'AND' vs '&&' as operator
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If you use AND and OR, you'll eventually get tripped up by something like this:
$this_one = true;
$that = false;
$truthiness = $this_one and $that;
Want to guess what $truthiness equals?
If you said false... bzzzt, sorry, wrong!
$truthiness above has the ...
Difference between local and global indexes in DynamoDB
...ndary index is
considered "global" because queries on the index can span all of the
data in a table, across all partitions.
Local secondary index — an index that has the same hash key as the
table, but a different range key. A local secondary index is "local"
in the sense that every p...
Why are regular expressions so controversial? [closed]
...ions. And not just slow, but the performance of the regex engine can be totally unpredictable when faced with arbitrary (user-supplied) inputs.
– Pacerier
Dec 1 '15 at 21:53
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