Installation

STIPS is a simulation tool that depends on other modules such as PSF and exposure time calculators. These underlying submodules need to be installed for STIPS to function properly along with their supporting datasets. There are multiple options for installation and they are listed in this section along with instructions.

STIPS Requirements

  • pandeia>=2025.9: Exposure time calculator.

  • stpsf>=2.0.0: Nancy Grace Roman PSF calculator. STIPS also requires that poppy, a support package used by STPSF (Formerly WebbPSF), have version >=1.0.3.

  • astropy: STIPS uses Astropy in order to read and write ASCII tables (specifically in the IPAC format) and FITS files, as well as to generate Sersic profile models (if any are in the generated scene).

  • montage_wrapper: STIPS uses montage to generate mosaics. It is only imported if STIPS is asked to generate a multi-detector image.

  • numpy: STIPS uses numpy extensively for almost everything that it does.

  • photutils: STIPS uses photutils to determine the flux inside the half-light radius in generated Sersic profiles.

  • synphot>=1.1.1 and stsynphot>=1.1.0: STIPS uses synphot and stsynphot to generate bandpasses, count rates, and zero points. Note that the reference data must also be downloaded, as described below in Installing with pip.

  • scipy: STIPS uses SciPy to manipulate its internal images (zoom and rotate).

  • esutil: Used for retrieving data from sqlite databases in the form of numpy arrays.

Warning

esutil is not installed by the STIPS setup.py file because its pip installation has errors. After installing STIPS, you must run pip install esutil --no-cache-dir to have esutil available.

Note

esutil is only needed if you are using stips.star_generator.

Finally, STIPS requires a set of data files whose location is marked by setting the environment variable stips_data, which will be installed as part of these instructions.

Installing Using a Package Manager and Source Code

STIPS can be installed using one of the YAML files provided in its source code. These YAML files define an environment that a package manager like Micromamba, Mamba, Conda, or another can read and install on your machine. (If you don’t have a package manager, follow any of the preceding links for installation instructions.) The YAML files include all packages required by STIPS. Please follow the steps below to install STIPS.

Installing as a User

  1. You will need to clone the STIPS source code from the spacetelescope/STScI-STIPS repository. cd into the directory where you would like to store the source code and run:

    git clone https://github.com/spacetelescope/STScI-STIPS.git

cd STScI-STIPS

  2. The environment file can be used in two ways:

    • To create a new environment named stips:

      conda env create -f environment.yml
conda activate stips

    • Or, to install to or update an existing environment:

      conda env update --name <EXISTING-ENV> --file environment.yml

(If you are using mamba, substitute it for conda in the commands above. If you are using micromamba, substitute it for conda and also remove env in the commands above.)

Installing as a Developer

  1. This step is identical to the first step of Installing as a User.

  2. Follow the second step of Installing as a User but using the environment_dev.yml file instead of environment.yml.

Installing with pip

While it is possible to install STIPS with pip instead of a package manager, we recommend the latter due to the aforementioned warning about using pip with the esutil package.

Downloading Required Reference Data

STIPS, Pandeia, and STPSF require additional reference datasets. You will need to download the data and add them to your environmental path.

  1. Add the following paths to your bash environmental path. It is recommended that you add the path to your .bash_profile file:

      export stips_data="<absolute_path_to_this_folder>/ref_data/stips_data"
      export STPSF_PATH="<absolute_path_to_this_folder>/ref_data/stpsf-data"
      export PYSYN_CDBS="<absolute_path_to_this_folder>/ref_data/grp/redcat/trds"
      export pandeia_refdata="<absolute_path_to_this_folder>/ref_data/pandeia_data-xxxx.x_roman"

# if your Pandeia installation is 2026.1 or higher, add the following:
export PSF_DIR="<absolute_path_to_this_folder>/ref_data/pandeia_psfs-xxxx.x_roman"

Note

Make sure that you have the correct version number for pandeia_refdata (replace the “x.x.x”).

  1. cd into the ref_data directory in your STScI-STIPS clone.

  2. Run the following code (after ensuring your package manager’s stips environment is active):

    python retrieve_stips_data.py

Caution

Running retrieve_stips_data.py will fetch the latest versions of each package’s reference data. If you have manually configured your software environment to use other versions of any of these packages, download their reference data separately and configure your environment variables appropriately to avoid confusion.

Testing Installation

To test if all the required files have been installed, please import STIPS in Python:

bash-3.2$ python3
Python 3.11.15 | packaged by conda-forge | (main, Mar  5 2026, 16:58:53) [Clang 19.1.7 ] on darwin
Type "help", "copyright", "credits" or "license" for more information.

>>> import stips

>>> print(stips.__env__report__)

You should receive an output of the following form:

STIPS Version x.y.z with Data Version a.b.c at /Some/Path/To/stips_data.

STIPS Grid Generated with STIPS Version x.y.z.

Pandeia Version YYYY.n with Data Version YYYY.n at /Some/Path/To/pandeia_refdata.

STPSF Version d.e.f with Data Version d.e.f at /Some/Path/To/stpsf_data_path.

Ignore the following warning message if it appears:

WARNING: stips_data environment variable not found. Falling back on local STIPS data.