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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 ...
Fluid or fixed grid system, in responsive design, based on Twitter Bootstrap
...etting confused about the various options in the twitter bootstrap grid , and how they go together.
5 Answers
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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...
Metadata file … could not be found error when building projects
...t, so no dll files existed from previou successfull builds. Fix the errors and make sure a referenced project builds correctly.
– Moulde
Jan 30 '13 at 9:29
9
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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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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...
Regular expression to get a string between two strings in Javascript
...ot consume any input. It is a zero-width assertion (as are boundary checks and lookbehinds).
You want a regular match here, to consume the cow portion. To capture the portion in between, you use a capturing group (just put the portion of pattern you want to capture inside parenthesis):
cow(.*)mi...
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
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