Ruby is best known as the language behind the rails web application framework. However, it is a very flexible general purpose language that can be used for tasks of direct interest to R Developers (parsing files, interacting with databases, processing XML or JSON, math functions, statistics, machine learning, etc).
If you do not have root access on a Linux server, you may still be able to install the ruby language and rubgems. Start by checking the version currently installed (if any):
whereis ruby
which ruby
ruby --version
Create or navigate to a temporary directory.
mkdir ~/tmp
cd ~/tmp
Get a source archive of ruby and ruby gems from RubyForge.
wget http://rubyforge.org/frs/download.php/25689/ruby-1.8.6-p110.tar.gz
Uncompress and extract the downloaded source into such like $HOME/tmp.
tar -xzvf ruby-1.8.6-p110.tar.gz
Change directory to the location of extracted sources.
cd ruby-1.8.6-p110
Run configure script with –prefix option set to $HOME (avoid permissions issues). This will result in an installation of ruby in your home directory.
./configure –prefix=$HOME
make
make install
Add $HOME/bin to your path (in ~/.bash_profile or other startup script).
export PATH=/home/username/bin/:.:$PATH
Verify the correct version was installed:
ruby --version
Keep in mind that various subdirectories will be created by this process (bin, lib, share).
Download Gems
wget http://rubyforge.org/frs/download.php/69366/rubygems-1.3.6.zip
Set GEM_HOME to a gems directory that you have write access to. Replace /home/username with your own home directory location. Use “pwd” to get correct syntax.
export GEM_HOME=/home/username/gems
Run the ruby gems setup program.
ruby setup.rb
Depending upon your environment, you may want to set up aliases, configure your PATH or other environmental variables.
alias ruby='~/bin/ruby'
export GEM_HOME=/home/csaternos/gems
export RUBYOPT=rubygems
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