How do I install ruby 2.0.0 correctly on Ubuntu 12.04?

Question

I have successfully installed rvm, but when I run the following commands

sudo apt-get update

Or:

rvm install 2         


        

Answer 1

Use rvm to install stable ruby:

curl -sSL https://get.rvm.io | bash -s stable --ruby

or, if you have rvm already, get stable version:

rvm get stable

Install ruby and use the specific version of ruby (remember to use login shell)

/bin/bash --login
rvm install 2.0.0
rvm use 2.0.0
rvm rubygems latest
ruby --version

As found on the official RVM website.

EDIT: As @prem points out run this at first and follow the above steps if there is a public key error

gpg --keyserver hkp://keys.gnupg.net --recv-keys \ 409B6B1796C275462A1703113804BB82D39DC0E3

Use rbenv to install ruby:

Install necessary dependancies:

sudo apt-get update && sudo apt-get install git-core curl zlib1g-dev \
build-essential libssl-dev libreadline-dev libyaml-dev libsqlite3-dev \
sqlite3 libxml2-dev libxslt1-dev libcurl4-openssl-dev \
python-software-properties libffi-dev

Install rbenv:

cd
git clone git://github.com/sstephenson/rbenv.git .rbenv
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.bash_profile
echo 'eval "$(rbenv init -)"' >> ~/.bash_profile

git clone git://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
echo 'export PATH="$HOME/.rbenv/plugins/ruby-build/bin:$PATH"' >> ~/.bash_profile
source ~/.bash_profile

Install ruby:

rbenv install -v 2.0.0