Lmod on Linux Hosts

If you can't find an application on an ECN supported Linux host try using the Lmod environment module system.

module avail

This command will show you the software available for loading using Lmod.

You will see something like:

------------------------------- /etc/modulefiles -------------------------------
   mpi/mpich-x86_64        mpi/mpich-3.2-x86_64        pkg/python3/3.7.4
   mpi/mpich-3.0-x86_64    mpi/openmpi3-x86_64  (D)

----------------------------- /etc/modulefiles/pkg -----------------------------
   python3/3.7.4

----------------------- /package/modulefiles/ecn/common ------------------------
   comsol/4.3b        gurobi/8.0.1            matlab/R2019a
   comsol/5.2a        intel/16.0.3            matlab/R2019b        (D)
   comsol/5.3a        intel/18.0.1     (D)    pointwise/18.3R1
   comsol/5.3         maple/2019              tecplot-360/2018R1.1
   comsol/5.4         mathematica/12.0        tecplot-rs/2017R1
   comsol/5.5  (D)    matlab/R2015a           thermocalc/2018b
   cplex/12.9         matlab/R2017a
   gams/27.2.0        matlab/R2018b

----------------------- /package/modulefiles/ecn/centos ------------------------
   abaqus/2019         ansys/2020R1           gcc/5.3.0
   ansys/15.0.7        ansysedt/19.0          gcc/6.3.0
   ansys/19.0          ansysedt/2019R2 (D)    gcc/7.1.0
   ansys/2019R2 (D)    ansysedt/2019R3        gcc/8.3.0    (D)
   ansys/2019R3        ansysedt/2020R1        texlive/2019

  Where:
   D:  Default Module

By default, no modules are loaded at login or when a terminal/console/shell is opened.

To then be able to use a specific application

module load matlab

This will load the default version of Matlab. Those are noted by the (D) next to them in the module avail command.

You can also load a specific version of an application, too.

module load matlab/R2015a

This will unload the version of matlab currently loaded if it is not R2015a.

NOTE: loading a module does not start that associated software. It only modifies your environment so you can then run the associated command(s) for that software.

Also, lmod modifies your shell environment. Previously you might have used an explicit path to run matlab like:

/usr/opt/bin/matlab -nodisplay < my_run.m

This is a perfectly reasonable and excellent way to do things. However, there is no /usr/opt/bin on systems that use lmod.

Instead you can just do:

matlab -nodisplay < my_run.m

You could use an explicit path for a program by doing something like:

which matlab

However, that path might change over time so we would recommend against it. At least on hosts using lmod.

Check this page if you have problems with lmd commands not being found.

More information about Lmod itself can be found at

https://lmod.readthedocs.io/en/latest/