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Grouping functions (tapply, by, aggregate) and the *apply family
Whenever I want to do something "map"py in R, I usually try to use a function in the apply family.
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How to generate JAXB classes from XSD?
...d we return a lot of XML. With this we decided to use JAXB. So far, we manually coded the Models for the XML.
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Named Branches vs Multiple Repositories
...ository. Your working copy will always reflect a single changeset, the so-called working copy parent changeset. Check this with:
% hg parents
Let's say that it reports [y]. You can see the heads with
% hg heads
and this will report [y] and [d]. If you want to update your repository to a clean ...
Ruby on Rails: How can I revert a migration with rake db:migrate?
...to revert.
eg. if you want to revert a migration with file name 3846656238_create_users.rb
rake db:migrate:down VERSION=3846656238
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Why does parseInt(1/0, 19) return 18?
...nity.
parseInt treats its first argument as a string which means first of all Infinity.toString() is called, producing the string "Infinity". So it works the same as if you asked it to convert "Infinity" in base 19 to decimal.
Here are the digits in base 19 along with their decimal values:
Base 1...
How do you load custom UITableViewCells from Xib files?
... simple: How do you load custom UITableViewCell from Xib files? Doing so allows you to use Interface Builder to design your cells. The answer apparently is not simple due to memory managment issues. This thread mentions the issue and suggests a solution, but is pre NDA-release and lacks code. He...
PHP Redirect with POST data
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Generate a form on Page B with all the required data and action set to Page C and submit it with JavaScript on page load. Your data will be sent to Page C without much hassle to the user.
This is the only way to do it. A redirect is a 303 HTTP header tha...
How do I test an AngularJS service with Jasmine?
... problem is that the factory method, that instantiate the service, is not called in the example above (only creating the module doesn't instantiate the service).
In order to the service to be instantiated angular.injector has to be called with the module where our service is defined. Then, we can a...
Filtering collections in C#
... ints that are > than 7, Where returns an
// IEnumerable<T> so a call to ToList is required to convert back to a List<T>.
List<int> filteredList = myList.Where( x => x > 7).ToList();
If you can't find the .Where, that means you need to import using System.Linq; at the to...
Is there a standardized method to swap two variables in Python?
...his tuple object have still been made, but it doesn't matter, Python internally knows where it is
then, the left-hand side is evaluated, that is to say the tuple is assigned to the left-hand side
as the left-hand side is composed of two identifiers, the tuple is unpacked in order that the first ide...