Version 17 (modified by toby, 10 years ago) (diff)


Installing GSAS-II on Mac OS X

Prerequisite: Before GSAS-II can be used on your computer, you must have Python installed with a number of required Python packages (see below.) You must also have the subversion (svn) package installed, which is standard on all Macs prior to Mountain Lion (10.8), but can be loaded easily at least on 10.9.

GSAS-II has been tested by us on Intel (i386) Macs running 10.5 (Leopard), 10.6 (Snow Leopard) and 10.7 (Lion). We have heard from people running with 10.8 (Mountain Lion) but have not tested this ourselves yet. Testing in 10.9 (Mavericks) is in progress. Getting GSAS-II to run on Macs running 10.4 or with a PPC (G4/G5) processor is likely possible, but will require considerable work since you would need to build python and its packages from source code and compile the GSAS-II Fortran code; this is not recommended except to the cognoscenti.

10.9 Users, please see these notes (probably appropriate for 10.8, too) before reading farther.

Quick Install Instructions

  1. We are recommending use of the older 32-bit EPDfree Python distribution; download the EPDfree 32-bit Mac installer from web page Users on 10.8 and 10.9 may want to try the 64-bit Canopy Express from Enthought downloads, but expect some bugs. At present both EPDfree and Canopy Express require administrator privileges to install.
  1. (For 10.7 or earlier, skip this step.) Install Subversion, if running Mountain Lion (OS X 10.8) or Mavericks (OS X 10.9), type svn in at a terminal window to get a prompt from OS X to download and install this directly from Apple.
  1. Download file file from ​ and move it to the location where you want GSAS-II to be installed.
  1. Start a terminal window and run the previous file by typing <path1>python <path2>, where <path1> is the location where the full python has been loaded. If you are not sure, you can type python on a line by itself and see if you are running EPD python. <path2>` will be where you have installed the file. Simply clicking on that file might work.
  1. Run GSAS-II with the file created by the bootstrap procedure.


Python is a computer scripting language, which means that one must have the Python interpreter installed on your Mac to run a Python program. Macs do come with python installed, but not with all the Python packages required by GSAS-II, so some Python software installation is required. Note that GSAS-II has not been fully tested on the Mac with wxPython 2.9, which is the first Mac release to support 64-bit Python.

We use the Enthought Python Distribution (EPD) package for our code development (Argonne has a site license) and have done just a bit of testing with the newer product, Enthought Canopy. The free versions of these packages will run GSAS-II, with addition of one small package that is self-installed (see below). While OS X does come with installed versions of Python, they are pretty old and do not contain all the packages GSAS-II needs, so adding the missing packages is probably not a good idea. Use of the Fink or DarwinPorts versions of Python is also not the best choice -- the GUI and graphics will be shown in X-windows rather than in Mac style. Note that at this time, Python 2.7 is recommended and probably required for GSAS-II. GSAS-II does not yet support Python 3.0+.

To get Canopy Express, use the "Get Canopy Express" button on See these notes for installation details.

For EPD free use the older EPDfree 32-bit Mac installer from web page Installation of EPD free from the .dmg is easy: click on the file to open it (that might happen automatically when you download it). In that new volume, you will see the EPD_free.mpkg installer. Click on that to start the installation process. It works best to run this from the account where you will run GSAS-II and supply the name of the admin account and its password when requested, as this will cause your login shell setup file to be updated so that directory /Library/Frameworks/Python.framework/Versions/Current/bin is in your path. (This is done by adding lines like this to file ~/.profile:

# Setting PATH for EPD-7.2-2
export PATH

Note on OS X 10.9 (and perhaps with prior versions), when first starting GSAS-II under EPD free, one will get a warning "to open fc-list, you need to install X11..." you can ignore that warning and press Cancel. (This warning occurred twice for me.) It then seems to go away.

  • ActiveState ActivePython is a possible alternative to EPD. This is also commercial licensed software, where there is a free version with no support. We have not tried this yet. If it works for you, please let us know.


If you are running 10.7 (Lion) or earlier, skip this step. For 10.8 (Mountain Lion) you must install the subversion (svn) package. To do this, type svn in a terminal window.

Alternately, install one of the following: Apple's Command Line Tools, or Apple's Xcode development environment, a 3rd party SVN package, or build from source code, see The Command Line Tools and Xcode can be downloaded from the Apple Developer's web site ( or can possibly be found on the OS X install DVD. A free 3rd party version of Subversion from WANdisco is here:

Compiling Fortran Code

Please skip this step, unless you have an older computer running OS X 10.4 or a PPC (G4, etc.) CPU or are not using Python 2.7.

GSAS-II requires a small number of Fortran routines that are incorporated as Python packages (.so files). If you use Python 2.7 and OS X 10.5 and 10.6+, GSAS-II should run with distributed files. If you are using less common options, you may need to compile the Fortran routines yourself using the NumPy f2py routine and the compiler of your choice. Both G77 and GFortran have worked on the Mac.

To help with compiling the programs, use the python scons routine inside the GSASII/fsource directory. If you are lucky, this routine will find the needed compiler and python program, set all options correctly for you and run all steps needed to prepare the .so files. This is done by

(1) opening a Terminal or xterm window,

(2) using the cd command to set your working directory to .../GSASII/fsource and

(3) simply typing "scons" in the window.

If you need to change any options, type "scons help" to see a list of the possible command-line arguments and the values for the options. For testing, help can be used with command-line options to see how they will change the variables.


We prefer that GSAS-II be installed using subversion so that it is easy to get updates (which are frequent). Fortunately, with OS X 10.5, 10.6 or 10.7, Macs come with subversion installed. (10.8 see above.) This procedure loads GSAS-II using subversion:

  1. Create a folder where you want to install GSAS-II.
  1. Download file file using this link:

or use this command:

curl >

  1. Move the file into the newly created GSAS-II folder
  1. Run the file by double-clicking on it or using the command python
  1. This creates a file that can be used to start GSAS-II either by clicking on the app or by dragging a file onto the app. Note that the app file can be dragged to the doc, but it cannot be moved to another folder. Instead, create an alias and move the alias where desired.

Note that GSAS-II can be updated at any time by reusing the file. This will download any newly created and modify any updated program files.


As of GSAS-II version 983 (July 7, 2013), a new app builder is used. This causes the name of the program to be listed as GSAS-II in the Mac menus and has better drag and drop support. If you downloaded a prior version of, update this file or else run the new file manually (be sure to use the Python needed for GSAS-II).

If you can help expand any of these instructions, discover new mechanisms for installing Python, or have problems getting this to work, please let me know.

Attachments (2)

Download all attachments as: .zip