Some software packages require certain settings in your user environment, like paths and environment variables. Instead of doing all of this by hand in your .bash_profile or .login, you can use the modules package to set up the appropriate user environment for you.

NOTE: some packages made available with the modules are also available in the standard directories. For example: there exists a file /usr/lib/libfftw3.so and there is also a module for the fftw3 library. The cause is that the installation of certain packages demand the installation of other packages (for example: the package scipy (scientific python) depends on the package fftw). This can be misleading and give rise to strange problems, but there are some reasons to provide the modules anyway:

• In most cases we provide a fortran library that can also be used with the Intel fortran compilers. In general, the fortran libraries from the standard (Debian) packages can only be used with gfortran (the GNU fortran compiler).
• By providing our own packages we can make sure that they are optimized for the Lisa system: examples are atlas and openmpi.
• Sometimes you need to initialize the module enviropment. The recipes for the different shells:

* bash: . /sara/sw/modules/module/init/bash
* csh:  source /sara/sw/modules/module/init/csh
* tcsh: source /sara/sw/modules/module/init/tcsh

• Detailed description of the usage of modules