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Grouping functions (tapply, by, aggregate) and the *apply family
...ed by the extremely popular plyr package, the base functions remain useful and worth knowing.
This answer is intended to act as a sort of signpost for new useRs to help direct them to the correct *apply function for their particular problem. Note, this is not intended to simply regurgitate or repla...
What is the minimum valid JSON?
...a JSON text as being a serialized object or array.
This means that only {} and [] are valid, complete JSON strings in parsers and stringifiers which adhere to that standard.
However, the introduction of ECMA-404 changes that, and the updated advice can be read here. I've also written a blog post on ...
Could not load file or assembly 'System.Net.Http.Formatting' or one of its dependencies. The system
...ally take these steps:
Go to the packages folder in the Windows Explorer and delete it.
Open Visual Studio and Go to Tools > Library Package Manager > Package Manager Settings and under the Package Manager item on the left hand side there is a "Clear Package Cache" button. Click this button ...
Fast and Lean PDF Viewer for iPhone / iPad / iOS - tips and hints?
...ively the same approach except :
I cache the generated image on the disk and always generate two to three images in advance in a separate thread.
I don't overlay with a UIImage but instead draw the image in the layer when zooming is 1. Those tiles will be released automatically when memory warnin...
How to change MySQL data directory?
...
Stop MySQL using the following command:
sudo /etc/init.d/mysql stop
Copy the existing data directory (default located in /var/lib/mysql) using the following command:
sudo cp -R -p /var/lib/mysql /newpath
edit the MySQL configuration file with the following...
What is the difference between static func and class func in Swift?
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Is it simply that static is for static functions of structs and enums, and class for classes and protocols?
That's the main difference. Some other differences are that class functions are dynamically dispatched and can be overridden by subclasses.
Protocols use the class keyword, b...
Image Processing: Algorithm Improvement for 'Coca-Cola Can' Recognition
... sample below, with the can recognized in the green rectangle with scale and rotation.
23 Answers
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How to obtain the start time and end time of a day?
How to obtain the start time and end time of a day?
14 Answers
14
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How to completely uninstall Visual Studio 2010?
I've been looking to find a CLEAN solution to completely and ultimately remove Visual Studio 2010 from my computer. When you install Visual Studio, it also installs a bunch of programs (about 55) in the add/remove programs panel ( appwiz.cpl ).
...
Difference between \w and \b regular expression meta characters
Can anyone explain the difference between \b and \w regular expression metacharacters? It is my understanding that both these metacharacters are used for word boundaries. Apart from this, which meta character is efficient for multilingual content?
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