Installing ASE, Asap and GPAW on a Mac

NEVER install Python packages into the MacOS version of Python, you risk breaking things! Instead, install a (more up to date) Python using Homebrew or Anaconda. This guide explains how to install our software using Homebrew.

ANACONDA USERS: If you use anaconda, you will only get the serial version of Asap (which is probably what you need anyway to run in e.g. Jupyter notebooks). To install with anaconda, first Install Xcode as described below, then make sure numpy, scipy and matplotlib are installed in Anaconda. Finally, Install ASE, Asap and GPAW as described in the very bottom of this document. Skip all steps in-between.

Install Xcode

Get Xcode from the App Store and install it. You also need to install the command line tools, do this with the command:

xcode-select --install

Install Homebrew

These instructions assume that you use the Homebrew package manager to install open-source software on your Mac. If you use MacPorts or fink, you will have to figure out yourself what to do - just follow the spirit of these instructions.

Install homebrew using the instructions on their home page: http://brew.sh

Basically, just copy the one-liner near the top of their page into a Terminal window.

Then you should insert the following lines near the top of your .bash_profile file to make sure that Homebrew’s stuff will take precedence over the system binaries:

# Homebrew needs this:
export PATH=/usr/local/bin:$PATH

Install Homebrew’s Python

Homebrew can use it’s own Python installation, or it can use the system’s Python installation. Using its own is strongly recommended, if you accidentally install something terrible you can always as a last resort delete everything homebrew-related and start over. If you have installed into the system Python installation cleanup after a mistake can be very difficult.

An alternative would be to use VirtualEnv to compartmentalize you Python packages. However, VirtualEnv does not work with parallel Asap or GPAW calculations!

Install Python:

brew install python

Check that you get Homebrew’s python:

which python

This should give you /usr/local/bin/python, if it gives /usr/bin/python you should fix your path in your .bash_profile file.

Install ASE prerequisites

ASE depends heavily on the NumPy package, which can be installed with Python’s default installer pip. The GUI also requires Matplotlib, and a few features depend on Scipy as well. Install them all:

pip install numpy scipy matplotlib

Install prerequisites for Asap and GPAW

You will need openmpi for parallel Asap or GPAW calculations (i.e. if you wish to use all the CPU cores in your computer). If you want to install GPAW, you will also need libxc:

brew install openmpi
brew install libxc

Install ASE, Asap and GPAW

You can now install ASE, Asap and GPAW following the normal installation procedure. The easiest is to use pip to install them:

pip install ase
pip install asap3
pip install gpaw

Note: You do not need Asap to run GPAW. If you want to do DFT calculations it is unlikely that you need Asap!

Note: You do not need GPAW to run Asap. If you want to run molecular dynamics using the EMT potential you probably do not need GPAW.

If you installed GPAW, you need to install its PAW setups too