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Sort rows in data.table in decreasing order on string key `order(-x,v)` gives error on data.table 1.
...l attempt and the following answer is no longer necessary.
You can use DT[order(-rank(x), y)].
x y v
1: c 1 7
2: c 3 8
3: c 6 9
4: b 1 1
5: b 3 2
6: b 6 3
7: a 1 4
8: a 3 5
9: a 6 6
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getting the last item in a javascript object
...
No. Order is not guaranteed in JSON and most other key-value data structures, so therefore the last item could sometimes be carrot and at other times be banana and so on. If you need to rely on ordering, your best bet is to go wi...
abort, terminate or exit?
...t successfully exits the
application, and calls atexit()
functions in LIFO order. I don't
normally see this in C++
applications, however, I do see it in
many unix based applications where it
sends an exit code at the end.
Usually a exit(0) indicates a
successful run of the application.
...
iPhone Keyboard Covers UITextField
...ViewController instance from the UIWindow.rootViewController hierarchy. In order to properly uncover UITextField/UITextView on it, topMostViewController.view's frame needs to be adjusted.
Step3:- Calculated expected move distance of topMostViewController.view with respect to first responded UITextF...
Pass in an array of Deferreds to $.when()
...er will require, that handler would need to process the arguments array in order to retrieve the result of each promise.
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Sorted collection in Java
...just for the purpose of having a sorted list. It is named (somewhat out of order with the other Sorted* interfaces) "java.util.PriorityQueue". It can sort either Comparable<?>s or using a Comparator.
The difference with a List sorted using Collections.sort(...) is that this will maintain a pa...
Using std Namespace
...er support for a non-throwing swap" from Effective C++, Third Edition. In order to have a generic, templated function use the 'best' swap method for a parameterized type, you need to make use of a using-declaration and argument dependant lookup (aka ADL or Koenig lookup):
template< typename T &...
Create a CSV File for a user in PHP
... to create the CSV, but miss a basic part of the question: how to link. In order to link to download of the CSV-file, you just link to the .php-file, which in turn responds as being a .csv-file. The PHP headers do that. This enables cool stuff, like adding variables to the querystring and customize ...
What is the max size of localStorage values?
Since localStorage (currently) only supports strings as values, and in order to do that the objects need to be stringified (stored as JSON-string) before they can be stored, is there a defined limitation regarding the length of the values.
...
Why should I use Google's CDN for jQuery?
...need to customize it. For example if you use Grunt to build the library in order to use only certain modules or setting the AMD name
When you are serving pages over SSL
that require jQuery. You should
serve the JavaScript over SSL as
well as your page to avoid security
problems and warnings.
Also...