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How do you delete a column by name in data.table?
...l remove column foo from the data.table df3:
# Method 1 (and preferred as it takes 0.00s even on a 20GB data.table)
df3[,foo:=NULL]
df3[, c("foo","bar"):=NULL] # remove two columns
myVar = "foo"
df3[, (myVar):=NULL] # lookup myVar contents
# Method 2a -- A safe idiom for excluding (possibly m...
What is the best way to compute trending topics or tags?
Many sites offer some statistics like "The hottest topics in the last 24h". For example, Topix.com shows this in its section "News Trends". There, you can see the topics which have the fastest growing number of mentions.
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JavaScript equivalent of PHP’s die
Is there something like "die" in JavaScript? I've tried with "break", but doesn't work :)
14 Answers
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How do I get current date/time on the Windows command line in a suitable format for usage in a file/
Update: Now that it's 2016 I'd use PowerShell for this unless there's a really compelling backwards-compatible reason for it, particularly because of the regional settings issue with using date . See @npocmaka's https://stackoverflow.com/a/19799236/8479
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How to permanently add a private key with ssh-add on Ubuntu? [closed]
I have a private key protected with a password to access a server via SSH.
13 Answers
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Python: Bind an Unbound Method?
In Python, is there a way to bind an unbound method without calling it?
5 Answers
5
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Change font color for comments in vim
...fault font color for comments which is dark blue to slightly yellow color. It is difficult to read on the black background.
Could you advise me how to change only this one color? I'm satisfied with the other colors.
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Can I call a constructor from another constructor (do constructor chaining) in C++?
... // combines two constructors (char) and (char, int)
// ...
};
Use an init method to share common code:
class Foo {
public:
Foo(char x);
Foo(char x, int y);
// ...
private:
void init(char x, int y);
};
Foo::Foo(char x)
{
init(x, int(x) + 7);
// ...
}
Foo::Foo(char x, int y)
{
ini...
Close Window from ViewModel
...mented an CloseWindow Method which takes a Windows as parameter and closes it. The window is passed to the ViewModel via CommandParameter. Note that you need to define an x:Name for the window which should be close. In my XAML Window i call this method via Command and pass the window itself as a par...
Detect HTTP or HTTPS then force HTTPS in JavaScript
Is there any way to detect HTTP or HTTPS and then force usage of HTTPS with JavaScript?
13 Answers
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