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Dynamically select data frame columns using $ and a character value
I have a vector of different column names and I want to be able to loop over each of them to extract that column from a data.frame. For example, consider the data set mtcars and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic s...
IPC performance: Named Pipe vs Socket
...y? I would prefer to use sockets because they can do two-way communication and are very flexible but will choose speed over flexibility if it is by considerable amount.
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rails 3.1.0 ActionView::Template::Error (application.css isn't precompiled)
...de a basic rails app with a simple pages controller with an index function and when I load the page I get:
14 Answers
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How to use OpenFileDialog to select a folder?
...he FolderBrowserDialog (FBD). I concur that the FBD is awful from a user standpoint.
– Michael Paulukonis
Apr 28 '15 at 15:09
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Modify UIImage renderingMode from a storyboard/xib file
...lass rather to do the key value setting. Because, it this easier to set up and we could avoid the number setting to the enumeration value. For example: ` @implementation TemplateRenderingImageView -(id)initWithCoder:(NSCoder *)aDecoder{ self = [super initWithCoder:aDecoder]; if (self) { ...
Can't install PIL after Mac OS X 10.9
I've just updated my Mac OS to 10.9 and I discovered that some (all?) of my Python modules are not here anymore, especially the Image one.
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Globally override key binding in Emacs
How can I set a key binding that globally overrides and takes precedence over all other bindings for that key? I want to override all major/minor mode maps and make sure my binding is always in effect.
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Not equal != operator on NULL
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<> is Standard SQL-92; != is its equivalent. Both evaluate for values, which NULL is not -- NULL is a placeholder to say there is the absence of a value.
Which is why you can only use IS NULL/IS NOT NULL as predicates for such situ...
Grab a segment of an array in Java without creating a new array on heap
... of an array. An example would be to get the byte array containing the 4th and 5th bytes of a byte array. I don't want to have to create a new byte array in the heap memory just to do that. Right now I have the following code:
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jQuery's .click - pass parameters to user function
...f the functionality introduced in version 1.4.3 of the jQuery click event handler.
It allows you to pass a data map to the event object that automatically gets fed back to the event handler function by jQuery as the first parameter. The data map would be handed to the .click() function as the first...