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Summarizing multiple columns with dplyr? [duplicate]
...it with the dplyr-syntax. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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Unable to import a module that is definitely installed
.../python2.6/site-packages/
Save the file, restart the Terminal, and you're done
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Check if the number is integer
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The last if else could be done with simply isTRUE(test). Indeed that is all you need to replace the if else clause and the return statements as R automatically returns the result of the last evaluation.
– Gavin Simpson
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How do I remove the space between inline/inline-block elements?
...TML source code to be
tampered with. Can this issue be solved with CSS alone?
It is possible to solve this problem with CSS alone, but there are no completely robust CSS fixes.
The solution I had in my initial answer was to add font-size: 0 to the parent element, and then declare a sensible fon...
Android - Set fragment id
...quely identify Fragments, but ViewGroups. These IDs are of containers that one or more fragments can be added to dynamically. Using such a method to identify Fragments would require you to add ViewGroups dynamically to the Layout for every Fragment you insert. That would be pretty cumbersome.
So if...
Eclipse Workspaces: What for and why?
...creating a directory and putting inside it (you don't have to do it, it's done for you) files that manage to tell Eclipse these information. All you have to do explicitly is to select the folder where these files will be placed. And this folder doesn't need to be the same where you put your source c...
How to modify a pull request on GitHub to change target branch to merge into?
...ation.
close the previous PR
reference the "old" pull request from the new one; eg. Supersedes #123 (as commented below by Rivera)
(original answer, valid only when creating the PR)
You could try and chose another base branch, as in "Changing the branch range and destination repository" (Clicki...
UIView with rounded corners and drop shadow?
...e clipped to bounds! The second, outer container view will house the first one, has the same frame, with just a drop shadow. I've done this quite a few times to combine a border, drop shadow, and corner radius. It's really annoying, but it works really well.
– Kpmurphy91
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What are the benefits of Java's types erasure?
...er. There is a fairly consistent message with even just the excerpts mentioned thus far:
It's funny when Java users complain about type erasure, which is the only thing Java got right, while ignoring all the things it got wrong.
I get huge benefits (e.g. parametricity) and nil cost (alleged cost i...
How to use 'find' to search for files created on a specific date? [closed]
...ution. I couldn't get -newermt to run on 2.6.18-348.18.1.el5 kernel, let alone newer kernels.
– DarkForce
May 20 '15 at 12:29
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