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How do you delete a column by name in data.table?
...hod 3 (could then assign to df3,
df3[, !"foo"]
though if you were actually wanting to remove column "foo" from df3 (as opposed to just printing a view of df3 minus column "foo") you'd really want to use Method 1 instead.
(Do note that if you use a method relying on grep() or grepl(), you need ...
how does Array.prototype.slice.call() work?
...ay, but I don't understand what happens when using Array.prototype.slice.call(arguments)
13 Answers
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Showing commits made directly to a branch, ignoring merges in Git
...using git, is there a way to show commits made to a branch, while ignoring all commits that were brought in by merging?
3...
How do I define global variables in CoffeeScript?
...
Since coffee script has no var statement it automatically inserts it for all variables in the coffee-script, that way it prevents the compiled JavaScript version from leaking everything into the global namespace.
So since there's no way to make something "leak" into the glob...
Changing website favicon dynamically
...wing example might not work in Safari or Internet Explorer.
/*!
* Dynamically changing favicons with JavaScript
* Works in all A-grade browsers except Safari and Internet Explorer
* Demo: http://mathiasbynens.be/demo/dynamic-favicons
*/
// HTML5™, baby! http://mathiasbynens.be/notes/document...
Most efficient way to concatenate strings in JavaScript?
...once.
is wrong, because it's based on a flawed test. That test never actually appends into the DOM.
This fixed test shows that creating the string all at once before rendering it is much, MUCH faster. It's not even a contest.
(Sorry this is a separate answer, but I don't have enough rep to comme...
how can I see what ports mongo is listening on from mongo shell?
...f (see Derick's answer below) or netstat -an to view what a process is actually doing. However, assuming you only have access to the mongo shell (which your question title implies), then you can run the serverCmdLineOpts() command. That output will give you all the arguments passed on the command ...
How do you turn off version control in android studio?
...I can't seem to turn off, or get out of version control to use the IDE normally again.
5 Answers
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How do I get the last four characters from a string in C#?
...of code (which the OP already knew) and cramming it onto one line is not really the same thing as one expression.
– Buh Buh
Jun 20 '11 at 15:39
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html select only one checkbox in a group
So how can I only allow a user to select only one checkbox?
16 Answers
16
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