Software Modules Tutorial

Modular software management allows a user to dynamically augment their environment with software that has been installed on the system.

Each module file contains the required information to configure the environment for that particular software package. As a user, you are able to load module files in your environment thereby making the software packages they describe available for use. More information about using the module command can be obtained by typing module help at the command line.

Command Summary

Some commonly used module command options:

Command Description
module list Lists all currently loaded software packages
module avail Displays a list of all software packages that have been compiled for the system
module load [software_package] Enables use of software_package by setting the appropriate environmental variables and adding the software binaries to your path
module swap [pgk1] [pkg2] Unloads software pkg1 and loads pkg2
module unload [software_package] Removes software_package from your path and unsets any environmental variables set by that package
module purge Unloads all currently loaded software packages
module help [software_package] Displays a description of software_package

Example

The following briefly shows how to load, swap, and unload a software package (in this case, the molecular dynamics visualization program VMD):

  1. Find the name of the modulefile you wish to load by typing the command:

    module avail

$ module avail

R/2.14
bino/1.3
gnuplot/4.4
matlab/2012a
pgi/2012
vmd/1.9
vmd/1.9.1(default)

  1. Verify VMD is not currently loaded by typing the command:

    module list

$ module list

Currently Loaded Modulefiles:
1) R/2.14
2) gnuplot/4.4

  1. To load the default version of a software module, just specify the name of the software module, in this case, “vmd”:

    module load vmd

  2. Verify the module has been loaded with the command:

    module list

$ module list

Currently Loaded Modulefiles:
1) R/2.14
2) gnuplot/4.4
3) vmd/1.9.1

VMD has now been loaded and can be invoked from the command line. If for some reason we need to switch to version 1.9 of VMD, the module swap command can be used as follows:

  1. Swap the default version of VMD (v1.9.1) for a different version (v1.9 for example):

    module swap vmd/1.9.1 vmd/1.9

  2. Verify the module has been swapped with:

    module list

$ module list

Currently Loaded Modulefiles:
1) R/2.14
2) gnuplot/4.4
3) vmd/1.9

Version 1.9 of VMD is now available on the command line instead of version 1.9.1. To remove VMD from your environment, use the module unload command:

  1. Unload VMD software package with:

    module unload vmd

  2. Verify the module has been removed with:

    module list

$ module list

Currently Loaded Modulefiles:
1) R/2.14
2) gnuplot/4.4

Further Assistance

To request software packages, build variants, specific versions or any other software package related questions please contact help@rcc.uchicago.edu