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How does one reorder columns in a data frame?
...mns like so df[,c(1,2,3,4)].
Note the first comma means keep all the rows, and the 1,2,3,4 refers to the columns.
To change the order as in the above question do df2[,c(1,3,2,4)]
If you want to output this file as a csv, do write.csv(df2, file="somedf.csv")
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How do you sort a dictionary by value?
...consisting of keys & values, by value. For example, I have a hash of words and respective frequencies, that I want to order by frequency.
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Reverse Y-Axis in PyPlot
I have a scatter plot graph with a bunch of random x, y coordinates. Currently the Y-Axis starts at 0 and goes up to the max value. I would like the Y-Axis to start at the max value and go up to 0.
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RSpec: how to test if a method was called?
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Sorry, I'm not understanding how this format of "to .. receive(:bar)" checks for the value of "called_bar" in this example. Can you explain that to me?
– ecoding5
Jun 29 '15 at 3:51
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Case sensitive Cmd+D in Sublime Text 2
In ST2 ⌘+D expands the selection to the next word, using case insensitive matching. Is it possible to match the word case sensitive?
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Change limit for “Mysql Row size too large”
...sibility that the above still does not resolve your issues. It is a known (and verified) bug with the InnoDB engine, and a temporary fix for now is to fallback to MyISAM engine as temporary storage. So, in your my.cnf file:
internal_tmp_disk_storage_engine=MyISAM
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Removing non-repository files with git?
I'm writing Autotools code and in the process of development, tons of files are generated.
1 Answer
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Looping a video with AVFoundation AVPlayer?
...ect as? AVPlayerItem {
playerItem.seek(to: CMTime.zero, completionHandler: nil)
}
}
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Python regular expressions return true/false
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Match objects are always true, and None is returned if there is no match. Just test for trueness.
if re.match(...):
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Using :after to clear floating elements
I have a list and the li's have a float:left; . The contents after the <ul> should be aligned correctly. Therefore i can build the following:
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