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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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Specify sudo password for Ansible
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You can pass variable on the command line via --extra-vars "name=value". Sudo password variable is ansible_sudo_pass. So your command would look like:
ansible-playbook playbook.yml -i inventory.ini --user=username \
--extra-var...
How to fix java.net.SocketException: Broken pipe?
...e commons http client to call url using post method to post the parameters and it is throwing the below error rarely.
10 A...
How to close this ssh tunnel? [closed]
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Assuming you ran this command: ssh -f user@mysql-server.com -L 3306:mysql-server.com:3306 -N as described in the post you linked.
A breakdown of the command:
ssh: that's pretty self-explanatory. Invokes ssh.
-f: (From the man ssh page)
Reques...
How to read an entire file to a string using C#?
... whether "quickest" means "least time to execute" or "least time to understand."
– bonh
Jun 22 '15 at 19:20
2
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In Clojure, when should I use a vector over a list, and the other way around?
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Once again, it seems I've answered my own question by getting impatient and asking it in #clojure on Freenode. Good thing answering your own questions is encouraged on Stackoverflow.com :D
I had a quick discussion with Rich Hickey, and here is the gist of it.
[12:21] <Raynes> Vectors a...
How to add multiple font files for the same font?
...le , but I don't get one thing. I have separate files for bold , italic and bold + italic . How can I embed all three files in one @font-face rule? For example, if I have:
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The function to show current file's full path in mini buffer
...t thing to do is to have your emacs window to always show your system-name and the full path of the buffer you're currently editing :
(setq frame-title-format
(list (format "%s %%S: %%j " (system-name))
'(buffer-file-name "%f" (dired-directory dired-directory "%b"))))
You can also d...
Removing an activity from the history stack
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You can achieve this by setting the android:noHistory attribute to "true" in the relevant <activity> entries in your AndroidManifest.xml file. For example:
<activity
android:name=".AnyActivity"
android:noHistory="true" />
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node.js execute system command synchronously
...sion 0.12 - so for a while) supports execSync:
child_process.execSync(command[, options])
You can now directly do this:
const execSync = require('child_process').execSync;
code = execSync('node -v');
and it'll do what you expect. (Defaults to pipe the i/o results to the parent process). Note t...