Sage is a very powerful computer algebra system. Especially nice is the LaTeX integration using sagetex. Here's how to set this up:

Install prerequisite libraries

sudo apt-get install build-essential m4 readline-common libreadline-dev texlive xpdf evince tk8.5-dev gfortran

Download the current version of the sources and compile them

wget http://mirror.switch.ch/mirror/sagemath/src/sage-4.8.tar
tar xvf sage-4.8.tar

Download the file for you platform from here http://www.sagemath.org/download-linux.html

Unpack/move the build or downloaded files to /opt, this gives you a directory /opt/sage-4.xy…

Make a symolic link to this directory:

sudo ln -s /opt/sage-4.... /opt/sage

Change the ownership of the files to root

sudo chown root:root /opt/sage/* -R

Run sage as root for the first time to update some paths which are absolute

cd /opt/sage-4....
sudo sage

After that, you should be able to run sage as a normal user

sage
sage: 2+2
4
sage:

If you get errors when starting up, then probably the first start as root has created some files in the directory ~./sage which now belong to root instead of you (USER)

cd .sage 
sudo chown $USER:$USER * -R
sage

Should now work.

Setting up sagetex for LaTeX

If you use LaTeX and want to integrate sage into your latex files (which gives you all the power of sage/maxima/maple/… directly inside you LaTeX file!):

  mkdir ~/texmf
  ln -s /opt/sage/local/share/texmf/tex/generic/sagetex/ ~/textmf/sagetex
  sudo texhash

Now you have the sagetex.sty file from the sage installation available. If you run texlive, it's a good idea to hunt down and rename the outdated sagetex.sty file which probably hangs around:

cd /usr/share/texmf-texlive/tex/latex/sagetex
ls
sudo mv sagetex.sty sagetex.sty.off
sudo texhash

To get started with sagetex read this guide: http://www.sagemath.org/doc/tutorial/sagetex.html

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