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Why is rbindlist “better” than rbind?
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rbindlist is an optimized version of do.call(rbind, list(...)), which is known for being slow when using rbind.data.frame
Where does it really excel
Some questions that show where rbindlist shines are
Fast vectorized merge of list of data.frames by row
Trouble...
How to handle initializing and rendering subviews in Backbone.js?
...fferent problems. I'm curious to know if there is a better way that solves all of the problems:
7 Answers
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How to have click event ONLY fire on parent DIV, not children?
... a little complex). In this case, because objects are being compared, it really doesn't make a difference, but you'll find that most people will still stick with the strict comparison.
– user1106925
Jul 9 '15 at 18:26
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Sqlite primary key on multiple columns
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@pratnala In standard SQL, yes. In SQLite, NULL is allowed in primary keys. This answer emphasizes that if you want more standard behavior, you need to add the NOT NULL yourself. My answer is just the very basic syntax for a multi-column primary key.
– B...
In absence of preprocessor macros, is there a way to define practical scheme specific flags at proje
... The simplest example is the DEBUG=1 macro that is defined by default for all Xcode projects in the default scheme for the Run build. One could query #ifdef DEBUG ... and make decisions in the code accordingly, even compiling out non-necessary code.
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How can I get a Dialog style activity window to fill the screen?
...tivity with the dialog theme set, and I want it to be full screen. I tried all sorts of things, even going through the WindowManager to expand the window to full width and height manually, but nothing works.
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How do I disable the resizable property of a textarea?
... elements:
textarea {
resize: none;
}
To disable it for some (but not all) textareas, there are a couple of options.
To disable a specific textarea with the name attribute set to foo (i.e., <textarea name="foo"></textarea>):
textarea[name=foo] {
resize: none;
}
Or, using an id...
ES6 class variable alternatives
...is syntax working.
The notes in the ES wiki for the proposal in ES6 (maximally minimal classes) note:
There is (intentionally) no direct declarative way to define either prototype data properties (other than methods) class properties, or instance property
Class properties and prototype data proper...
Defining an abstract class without any abstract methods
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Of course.
Declaring a class abstract only means that you don't allow it to be instantiated on its own.
Declaring a method abstract means that subclasses have to provide an implementation for that method.
The two are separate concepts, though obviously you can't have an abstract method ...
What does gcc's ffast-math actually do?
...tside of IEEE standards, but I can't seem to find information on what is really happening when it's on. Can anyone please explain some of the details and maybe give a clear example of how something would change if the flag was on or off?
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