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Modules Software Environment Manager on Quest

Quest uses Environment Modules to give users access to the software installed on Quest.

Modules are used to manage:

• multiple versions of applications, tools and libraries

• software where complex changes to the environment are necessary

• software where name conflicts with other software would cause problems

Loading a module for a particular piece of software often adds the path to the executable to $PATH, the path to the library to $LD_LIBRARY_PATH, and so on. Loading a module, then, relieves the user of having to remember or look up and type long path names.

Available Modules

Use the command

module avail

to list all modules available on Quest.

A listing of key software packages can also be found on the Quest Software page.

Loading a Module

To access almost every software application on Quest, you must first load the appropriate module:

module load <modulename>

Then you can reference software commands by name.

Example

module load python
python myscript.py

The module load command will typically be part of your job submission script.

Module Versions

There are multiple versions of many software programs on Quest. Modules are named with the format softwarename/version. For example, if you look at the modules available for Python, you'll see several versions:

module avail python

---------------------------------------- /software/Modules/3.2.9/modulefiles -----------------------------------------
python/2.7.13            python/ActivePython-3.2  python/anaconda(default) python/anaconda3.6
python/ActivePython-2.7  python/Canopy            python/anaconda3         python/epd-7.3-2

(default) indicates which module will be loaded if you don't specify the version (e.g. module load python). Defaults can change over time, however, so it is strongly recommended that you always specify the module version even if you are using the default version. For example,

module load python/anaconda

Useful Module Commands

Command	Action
module avail	Shows the available software packages
module avail <search>	Shows all modules that have <search> in the main part of the name (not in the version, which comes after the /). <search> is case sensitive. This is useful for viewing the versions available for a particular program instead of having to sort through the long list of all modules.
module list	Shows which modules are currently loaded
module load <module>	Loads a software package’s path information into your local environment so your session can find the software to run it
module purge <module>	Takes the software package’s information out of your local environment; this is generally more reliable that module unload
module purge all	Unloads all of the module packages currently in your local environment
module display	Displays the changes that are made to the environment by loading module foo without actually loading it

See Also:

• Quest Quick Start Guide
• Software on Quest