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Determine the number of NA values in a column
...unt the number of NA values in a data frame column. Say my data frame is called df , and the name of the column I am considering is col . The way I have come up with is following:
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Git: which is the default configured remote for branch?
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Wouldn't this also be set if the OP did git pull hub master?
– Ryan Bigg
Jan 31 '11 at 10:46
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How can I convert immutable.Map to mutable.Map in Scala?
...liased imports, but bear in mind that sacrificing immutability is very non-idiomatic for Scala, not exactly the sort of thing I'd enourage by making it look even easier... Out of curiosity, how else could you propose doing it more cleanly, if not via a copy?
– Kevin Wright
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.gitignore file, where should I put it in my xcode project?
...my XCode4 project, but where should I put the .gitignore file?, is it inside the .git folder? or out? The .git is in same folder with the ProjectName.xcodeproj file
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Getting started with Haskell
...x = x and x <> (y <> z) = (x <> y) <> z. These are called identity and associativity laws. Many types are Monoids, such as numbers, with mempty = 0 and <> = +. This is useful in many situations.
Arrows: Arrows are a way of representing computations that take an input a...
jquery-ui-dialog - How to hook into dialog close event
... Jake N - You need to actually write a function accessible to the dialog called 'CloseFunction' for this to work, for example just above you could write var CloseFunction = function() { //Do your custom closing stuff here };
– Adam Diament
Jul 24 '14 at 18:0...
JavaScript: remove event listener
... if(click == 50) {
this.removeEventListener('click',arguments.callee,false);
}
Should do it.
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How to convert date to timestamp?
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There are two problems here.
First, you can only call getTime on an instance of the date. You need to wrap new Date in brackets or assign it to variable.
Second, you need to pass it a string in a proper format.
Working example:
(new Date("2012-02-26")).getTime();
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How to remove all leading zeroes in a string
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$str = ltrim($str, '0') ?: '0'; -- no redundant trim call.
– mickmackusa
Jun 26 at 16:23
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Regular expression to match DNS hostname or IP Address?
... expressions separately or by combining them in a joint OR expression.
ValidIpAddressRegex = "^(([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])\.){3}([0-9]|[1-9][0-9]|1[0-9]{2}|2[0-4][0-9]|25[0-5])$";
ValidHostnameRegex = "^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za...