Loading ISSM

By default, MATLAB and Python cannot locate ISSM and its external packages. We outline here how to load ISSM in your chosen interface.

Environment

First, we need to make sure our interface can find ISSM and its external packages by running,

bash, zsh

export ISSM_DIR=<ISSM_PATH>
source ${ISSM_DIR}/etc/environment.sh

csh

setenv ISSM_DIR <ISSM_PATH>
source ${ISSM_DIR}/etc/environment.csh

where <ISSM_PATH> is the path to ISSM on disk (ex: ${HOME}/ISSM/src). This works whether you downloaded one of our precompiled distributables or compiled ISSM from source.

Scripting Interfaces

MATLAB

Note

There does not currently exist a method for starting the MATLAB GUI using its launcher icon with ISSM loaded.

Start MATLAB in a terminal by running,

matlab

If the matlab executable is not on your environment’s path, you will need to add its parent directory to the PATH environment variable, create an alias for matlab, or start MATLAB with the full path to the matlab executable.

After starting MATLAB, you must tell it where to find ISSM’s binaries and libraries by running,

addpath <ISSM_PATH>/bin <ISSM_PATH>/lib

again, where <ISSM_PATH> is the path to ISSM on disk. Alternatively, you can use the ‘Set Path’ dialog to add these paths manually. If you installed ISSM by downloading one of our precompiled distributables, you will also need to run,

addpath <ISSM_PATH>/share

Yet another alternative is to feel the addpath command as a statement to the matlab startup command, for example with,

matlab -r 'addpath ${ISSM_DIR}/bin ${ISSM_DIR}/lib'

You can verify that ISSM is findable by running,

issmversion

which should print a message similar to,

Ice-sheet and Sea-level System Model (ISSM) Version 4.22
(website: http://issm.jpl.nasa.gov contact:issm@jpl.nasa.gov)

Build date: Wed Sep 18 14:00:06 PDT 2023
Copyright (c) 2009-2023 California Institute of Technology

    to get started type: issmdoc

To avoid having to manually load ISSM each time you start up MATLAB, you might create an alias in your shell configuration file like,

alias matlab-issm="matlab -r 'addpath ${ISSM_DIR}/bin ${ISSM_DIR}/lib'"

If you will not be using MATLAB’s GUI, you might create aliases like,

alias matlab_no_gui="matlab -nosplash -nodesktop -nodisplay"
alias matlab-no_gui-issm="matlab -r 'addpath ${ISSM_DIR}/bin ${ISSM_DIR}/lib'"

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Python

Before starting Python, activate the virtual environment that you set up during installation with, for example,

source ${HOME}/.venv/ISSM/bin/activate

After starting Python, you must tell it where to find ISSM’s binaries and libraries by running,

import os
import sys
ISSM_DIR = os.getenv('ISSM_DIR')
sys.path.append(ISSM_DIR + '/bin')
sys.path.append(ISSM_DIR + '/lib')

If you installed ISSM by downloading one of our precompiled distributables, you will also need to run,

sys.path.append(os.getenv('ISSM_DIR') + '/share')

You can verify that ISSM is findable by running,

from issmversion import issmversion

which should print a message similar to,

Ice-sheet and Sea-level System Model (ISSM) Version 4.22
(website: http://issm.jpl.nasa.gov contact:issm@jpl.nasa.gov)

Build date: Wed Sep 18 14:00:06 PDT 2023
Copyright (c) 2009-2023 California Institute of Technology

To avoid having to manually load ISSM each time you start up Python, you might create a startup script, for example, ${HOME}/ISSM/bin/sitecustomize.py with the following contents,

#!/usr/bin/env python3
import os
import sys
ISSM_DIR = os.getenv('ISSM_DIR')
sys.path.append(ISSM_DIR + '/bin')
sys.path.append(ISSM_DIR + '/lib')

Then, add the following to the bottom of your virtual environment activation script (again, for example, ${HOME}/.venv/ISSM/bin/activate):

export PYTHONPATH="${HOME}/ISSM/bin:${PYTHONPATH}"

ISSM should now be findable by Python whether you are in an interactive or non-interactive session as long as you have first activated your virtual environment.

---

Development Build

If you configured and compiled ISSM for development, you will have to load ISSM a bit differently.

MATLAB

addpath <ISSM_PATH>/src/m/dev
devpath

again, where <ISSM_PATH> is the path to ISSM on disk.

Python

Before starting Python, run,

export PYTHONPATH="${ISSM_DIR}/src/m/dev"
export PYTHONSTARTUP="${PYTHONPATH}/devpath.py"

For IPython users, instead launch the interface with,

ipython -i ${ISSM_DIR}/src/m/dev/devpath.py