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Subset of rows containing NA (missing) values in a chosen column of a data frame
....na() instead. This should do it:
new_DF <- DF[rowSums(is.na(DF)) > 0,]
or in case you want to check a particular column, you can also use
new_DF <- DF[is.na(DF$Var),]
In case you have NA character values, first run
Df[Df=='NA'] <- NA
to replace them with missing values.
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How do I wait for an asynchronously dispatched block to finish?
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Trying to use a dispatch_semaphore. It should look something like this:
dispatch_semaphore_t s...
Android EditText delete(backspace) key event
...anampullan
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In what areas might the use of F# be more appropriate than C#? [closed]
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edited May 8 '10 at 14:01
community wiki
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No line-break after a hyphen
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Try using the non-breaking hyphen &#8209;. I've replaced the dash with that character in you...
Javascript: How to detect if browser window is scrolled to bottom?
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answered Feb 25 '12 at 0:03
mVChrmVChr
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What's the best way to do “application settings” in Android? [closed]
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Many applications may provide a way to capture user preferences on the settings of a specific ap...
Calc of max, or max of calc in CSS
... them.
Therefore the original example can be written as:
max-width: max(500px, 100% - 80px);
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UIRefreshControl on UICollectionView only works if the collection fills the height of the container
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LarryLarry
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What are the benefits of learning Vim? [closed]
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I've been using vi and vim also for some 20 years, and I'm still learning new things.
David Rayner's Best of Vim Tips site is an excellent list, though it's probably more useful once you have some familiarity with vim.
I also want to mention the ViEmu site which ha...