GNU Octave is a high-level interpreted language, primarily intended for numerical computations. It provides capabilities for the numerical solution of linear and nonlinear problems, and for performing other numerical experiments. It also provides extensive graphics capabilities for data visualization and manipulation. Octave is normally used through its interactive command line interface, but it can also be used to write non-interactive programs. The Octave language is quite similar to Matlab so that most programs are easily portable. Read more here.
For a list of available modules, type:
$ ml av octave ------------------------------- /apps/modules/math ------------------------------- Octave/6.3.0-intel-2020b-without-X11
Modules and Execution¶
To load the latest version of Octave load the module:
$ ml Octave
Octave on clusters is linked to a highly optimized MKL mathematical library. This provides threaded parallelization to many Octave kernels, notably the linear algebra subroutines. Octave runs these heavy calculation kernels without any penalty. By default, Octave would parallelize to 128 threads on Karolina. You may control the threads by setting the
OMP_NUM_THREADS environment variable.
To run Octave interactively, log in with the
ssh -X parameter for X11 forwarding. Run Octave:
To run Octave in batch mode, write an Octave script, then write a bash jobscript and execute via the
qsub command. By default, Octave will use 128 threads on Karolina when running MKL kernels.
#!/bin/bash # change to local scratch directory DIR=/scratch/project/PROJECT_ID/$PBS_JOBID mkdir -p "$DIR" cd "$DIR" || exit # copy input file to scratch cp $PBS_O_WORKDIR/octcode.m . # load octave module ml Octave/6.3.0-intel-2020b-without-X11 # execute the calculation octave -q --eval octcode > output.out # copy output file to home cp output.out $PBS_O_WORKDIR/. #exit exit
This script may be submitted directly to the PBS workload manager via the
qsub command. The inputs are in the octcode.m file, outputs in the output.out file. See the single node jobscript example in the Job execution section.
The Octave c compiler
mkoctfile calls the GNU GCC 6.3.0 for compiling native C code. This is very useful for running native C subroutines in Octave environment.
$ mkoctfile -v mkoctfile, version 6.3.0
Octave may use MPI for interprocess communication This functionality is currently not supported on the clusters. In case you require the Octave interface to MPI, contact support.