Getting the source code

To work with PTS you need to copy the Python source code to your local file system. First create a directory hierarchy that will hold the PTS source code and run-time information. The top-level directory can have any name (for example PTS) and can be located anywhere (for example in your home directory), but the subdirectories should be named as indicated below. Execute the following commands in a Terminal window to create the PTS directory in your home folder.

cd
mkdir PTS
cd PTS
mkdir run
mkdir pts

The PTS source code is available from the public PTS GitHub repository. While any user can freely retrieve the code from this repository (even anonymously), only the SKIRT team has write access to it. To obtain the code, in a Git Bash terminal, navigate to the PTS directory and execute::

git clone https://github.com/SKIRT/PTS9.git pts

To update your local copy of the source code after changes were made to the repository from which you cloned it, use:

git pull

Configuring PTS paths and aliases

It is important that your Python install can automatically locate the PTS source code so that it can execute PTS commands and import PTS packages regardless of the current directory. Furthermore it is handy to provide an alias so that you can easily access PTS from the command line.

Configure the Python path by opening Settings and searching for environment variables, then clicking "edit system environment variables". A pop-up window opens, which has a button "Environment variables" at the bottom. After clicking this button, a new pop-up window appears, where after clicking "New..." a new environment variable can be created with name PYTHONPATH and value ~/PTS (where ~ is the actual path of the directory).

Create an alias by executing:

doskey pts=python -m pts.do $*

However this alias is not remembered after closing the terminal window. As a workaround, just execute this line each time you want to use PTS.

To make the alias persistent when using Anaconda/Miniconda, find the location of the anaconda3/Scripts/activate.bat file (usually located somewhere like C:/Users/user/anaconda3/Scripts/activate.bat on Windows 10) and add the doskey command after the initial setting of arguments, e.g.:

@REM user added aliases
doskey pts=python -m pts.do $*
cls

Testing the PTS installation

You can run a basic test of your PTS installation by entering the following command line:

pts try me

which should produce a response similar to the following:

03/06/2019 16:52:05.043   Starting admin/try_do...
03/06/2019 16:52:05.043   Command line arguments are:
03/06/2019 16:52:05.043     Fixed string:    me
03/06/2019 16:52:05.043     Optional string: PTS is great
03/06/2019 16:52:05.043     Float number:    3.14
03/06/2019 16:52:05.043     Integer number:  7
03/06/2019 16:52:05.043   Finished admin/try_do.

Listing Python package dependencies

You may need to install additional third-party Python packages on which the PTS code depends. To assist with this process, the list_dependencies command script lists all packages referred to by the PTS code, including an indication of whether each package is already installed or not:

$ pts list_dependencies
  Starting admin/list_dependencies...
  PTS depends on 32 packages:
    argparse -- installed
    astropy -- installed
    datetime -- installed
    ...
!   reportlab -- NOT INSTALLED
    ...
    scipy -- installed
    zipfile -- installed
 Finished admin/list_dependencies.

The list includes both standard and third-party packages. Because the standard packages are built into the regular Python distribution, they will always be marked as "installed".

Some dependencies are optional and will be invoked only when the related PTS functionalty is actually used. The fsps package is an example of this.