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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...
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...
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...
'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 ...
Can I restore a single table from a full mysql mysqldump file?
I have a mysqldump backup of my mysql database consisting of all of our tables which is about 440 megs. I want to restore the contents of just one of the tables from the mysqldump. Is this possible? Theoretically, I could just cut out the section that rebuilds the table I want but I don't even know ...
Does JavaScript have a built in stringbuilder class?
... strings with the + or += operator are extremely slow on IE. This is especially true for IE6. On modern browsers += is usually just as fast as array joins.
When I have to do lots of string concatenations I usually fill an array and don't use a string builder class:
var html = [];
html.push(
"&l...
CSS: How to position two elements on top of each other, without specifying a height?
...exactly on top of each other. However, when I do that, the formatting gets all screwed up because the containing DIV acts like there is no height. I think this is the expected behavior with position:absolute but I need to find a way to position these two elements on top of each other and have the ...
Jquery - How to make $.post() use contentType=application/json?
... to
1.Modify the source to make $.post always use JSON data type as it really is just a shortcut for a pre configured $.ajax call
Or
2.Define your own utility function that is a shortcut for the $.ajax configuration you want to use
Or
3.You could overwrite the $.post function with your own i...
jquery.validate.unobtrusive not working with dynamic injected elements
...ate it to include the code in the comments otherwise it can break. Specifically, change the two selector lines to double quote the id.
– Ryan O'Neill
Jul 14 '11 at 19:50
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