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How to change language settings in R
...env() function. My R session defaults to English, so I'll set it to French and then back again:
> Sys.setenv(LANG = "fr")
> 2 + x
Erreur : objet 'x' introuvable
> Sys.setenv(LANG = "en")
> 2 + x
Error: object 'x' not found
A list of the abbreviations can be found here.
Sys.getenv() g...
Why can't I use Docker CMD multiple times to run multiple services?
... really is runtime information. Just like EXPOSE, but contrary to e.g. RUN and ADD. By this, I mean that you can override it later, in an extending Dockerfile, or simple in your run command, which is what you are experiencing. At all times, there can be only one CMD.
If you want to run multiple ser...
What's the valid way to include an image with no src?
...hich won't cause server hits. I recently had a similar issue with iframes and determined //:0 to be the best option. No, really!
Starting with // (omitting the protocol) causes the protocol of the current page to be used, preventing "insecure content" warnings in HTTPS pages. Skipping the host n...
What is a tracking branch?
...a direct relationship to a remote branch. If you’re on a tracking branch and type git push, Git automatically knows which server and branch to push to. Also, running git pull while on one of these branches fetches all the remote references and then automatically merges in the corresponding remote ...
How can I use tabs for indentation in IntelliJ IDEA?
...e:
File > Settings... > Editor > Code Style > Java > Tabs and Indents > Use tab character
File > Other Settings > Default Settings... > Editor > Code Style > Java > Tabs and Indents > Use tab character
File > Settings... > Editor > Code Style > D...
Get records with max value for each group of grouped SQL results
...alue for.
You avoid complicated subqueries that try to find the max() etc, and also the problems of returning multiple rows when there are more than one with the same maximum value (as the other answers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL synta...
Mercurial error: abort no username supplied
...install directory (C:\Program Files\Mercurial\Mercurial.ini on my machine)
and copy it to your user home dir (C:\Documents and Settings\myName on winXP).
On a Windows 7 install there is no default .ini, you will need to create a new one in C:\Users\myName.
Then edit that .ini file. Find this area....
Need some clarification about beta/alpha testing on the developer console
The Android developer console has 3 tabs for publishing the app's apk file:
alpha, beta and production, as shown here:
4 An...
What is the difference between and ?
What is the difference between <section> and <div> in HTML ? Aren't we defining sections in both cases?
...
How to make a node.js application run permanently?
On a Debian server, I installed Node.js. I understand how to launch an app from putty with this command line:
19 Answers
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