Fix/bug review

.github/workflows/ci.yml

@@ -23,7 +23,6 @@ concurrency:
 
 env:
   CI_PROJECT_DIR: ${{ github.workspace }}
-  GIT_LFS_SKIP_SMUDGE: 1
 
 jobs:
   test:
@@ -39,7 +38,6 @@ jobs:
     - uses: actions/checkout@v4
       with:
         submodules: 'recursive'
-        lfs: false
         token: ${{ github.token }}
     - name: Set up Python ${{ matrix.python-version }}
       uses: actions/setup-python@v5
@@ -50,15 +48,11 @@ jobs:
       run: |
         # Install dependencies
         sudo apt-get update
-        sudo apt-get install build-essential git git-lfs python3 python3-setuptools python3-venv graphviz cmake
+        sudo apt-get install build-essential git python3 python3-setuptools python3-venv graphviz cmake
 
         # Initialize and update submodules
         git submodule update --init --recursive
 
-        # Install Git LFS and pull LFS objects
-        # git lfs install
-        # git lfs pull
-
         # Upgrade pip and install Python dependencies
         python -m pip install --upgrade pip setuptools flake8
         python -m pip install -r requirements.txt
@@ -77,12 +71,6 @@ jobs:
         # Use the actions/setup-python toolchain and avoid Homebrew updates,
         # which can fail CI when the hosted runner's brew state is stale.
         python -m pip install --upgrade pip setuptools flake8 cmake
-
-        # Make LFS usable if the runner already has it, but do not require
-        # Homebrew just for CI wheel/import checks.
-        if command -v git-lfs >/dev/null 2>&1; then
-          git lfs install --skip-repo
-        fi
         git config --global credential.helper ""   # avoid Keychain prompts
 
         # Use the actions/setup-python toolchain consistently

.github/workflows/python-publish.yml

@@ -25,9 +25,7 @@ jobs:
       - name: Install dependencies
         run: |
           sudo apt-get update
-          sudo apt-get install build-essential git git-lfs cmake
-          git lfs install
-          git lfs pull
+          sudo apt-get install build-essential git cmake
           python -m pip install --upgrade pip build twine
           python -m pip install -r requirements.txt
 

MANIFEST.in

@@ -11,4 +11,3 @@ recursive-include pybind11/include/ *
 include pybind11/CMakeLists.txt
 include pybind11/LICENSE
 recursive-include pybind11/tools *
-recursive-include ssapy/data *

README.rst

@@ -29,6 +29,9 @@ wrappers around coordinate conversions, Lambertian magnitude / brightness
 calculations, and related extensions, see the companion project
 `SSAPy-Toolkit <https://github.com/llnl/SSAPy-Toolkit>`__.
 
+Optional packaged datasets are available with ``llnl-ssapy[data]``. Install
+``llnl-ssapy[all-data]`` to install every split ``ssatk-data-*`` distribution.
+
 SSAPy includes:
 
 - Ability to define satellite parameters (area, mass, radiation and drag coefficients, etc.)

docs/source/api.rst

@@ -20,6 +20,7 @@ and/or heavy dependencies.  Below lists the packages available in the ``ssapy``
       ssapy.constants
       ssapy.correlate_tracks
       ssapy.ellipsoid
+      ssapy.ephemeris
       ssapy.gravity
       ssapy.io
       ssapy.linker

docs/source/installation.rst

@@ -19,22 +19,22 @@ These requirements can be easily installed on most modern macOS and Linux system
        .. code-block:: console
 
           apt update
-          apt install build-essential git git-lfs python3 python3-distutils python3-venv graphviz
+          apt install build-essential git python3 python3-distutils python3-venv graphviz
 
     .. tab:: RHEL
 
        .. code-block:: console
 
           dnf install epel-release
           dnf group install "Development Tools"
-          dnf install git git-lfs gcc-gfortran python3 python3-pip python3-setuptools graphviz
+          dnf install git gcc-gfortran python3 python3-pip python3-setuptools graphviz
 
     .. tab:: macOS Brew
 
        .. code-block:: console
 
           brew update
-          brew install gcc git git-lfs python3 graphviz
+          brew install gcc git python3 graphviz
 
 Installation
 ------------
@@ -45,6 +45,30 @@ As the package has been published on `PyPI <https://pypi.org/project/llnl-ssapy/
 
    pip install llnl-ssapy
 
+SSAPy's data (ephemerides, gravity models, textures) is installed with it
+from the ``llnl-ssapy-data`` package; no Git LFS is needed.
+
+Planetary ephemerides
+^^^^^^^^^^^^^^^^^^^^^
+
+SSAPy uses JPL DE440 by default, from the short kernel ``de440s.bsp``
+(1849-2150). A 1900-2150 excerpt of DE430 is also installed for reproducing
+results from SSAPy 1.1.10 and earlier; select it with
+``ssapy.ephemeris.set_planetary_ephemeris("de430")`` or
+``SSAPY_EPHEMERIS=de430``.
+
+For epochs outside those spans SSAPy downloads a longer kernel of the same
+ephemeris from NAIF (``de440.bsp`` or ``de430.bsp``, 1550-2650, 120 MB) and,
+for DE440 beyond 1550-2650, DE441 (1.65 GB per half), checks its SHA-256,
+caches it in ``~/.cache/ssapy`` (``SSAPY_DATA_CACHE``), and warns before
+downloading. Set ``SSAPY_EPHEMERIS_DOWNLOAD=0`` to forbid downloads, for
+example on compute nodes without network access, and prefetch on a node that
+has it:
+
+.. code-block:: console
+
+   SSAPY_DATA_CACHE=/shared/ssapy-cache python -c "import ssapy.ephemeris as e; e.fetch()"
+
 Orekit dependency
 ^^^^^^^^^^^^^^^^^
 

docs/source/tables/system_prerequisites.csv

@@ -3,5 +3,4 @@ Python, 3.10--3.12, , Interpreter
 C/C++ Compilers, , , Building software
 make, , , Build software
 git, , , Manage software repositories
-git-lfs, , , Track large binary files
 graphviz, , , Local documentation building

pyproject.toml

@@ -31,6 +31,22 @@ dependencies = [
 ]
 
 [project.optional-dependencies]
+data = [
+    "ssatk-data-core==0.0.1",
+    "ssatk-data-gravity==0.0.1",
+    "ssatk-data-lunar==0.0.1",
+    "ssatk-data-lunar-gravity==0.0.1",
+]
+
+all-data = [
+    "ssatk-data-core==0.0.1",
+    "ssatk-data-gravity==0.0.1",
+    "ssatk-data-lunar==0.0.1",
+    "ssatk-data-lunar-gravity==0.0.1",
+    "ssatk-data-propulsion==0.0.1",
+    "ssatk-data-benchmarks==0.0.1",
+]
+
 dev = [
     "pytest",
     "pytest-cov",
@@ -70,7 +86,7 @@ packages = { find = { include = ["ssapy", "ssapy.*"], namespaces = true } }
 include-package-data = true
 
 [tool.setuptools.package-data]
-ssapy = ["*.cpp", "*.h", "data/*"]
+ssapy = ["*.cpp", "*.h"]
 
 [tool.pytest.ini_options]
 testpaths = ["tests"]

requirements.txt

@@ -2,6 +2,7 @@ graphviz
 numpy
 scipy
 jplephem
+llnl-ssapy-data>=0.2.0
 astropy
 pyerfa
 emcee

setup.py

@@ -45,7 +45,6 @@ def build_extension(self, ext):
     ext_modules=[CMakeExtension("ssapy._ssapy")],
     cmdclass={"build_ext": CMakeBuild},
     packages=find_namespace_packages(include=["ssapy", "ssapy.*"]),
-    package_data={'ssapy': ['data/*']},
     zip_safe=False,
     include_package_data=True,
 )

skills.md

@@ -115,11 +115,15 @@ r, v = rv(orbit, times, propagator=KeplerianPropagator())
 
 ## Data and Binary Rules
 
-SSAPy currently includes required package data under `ssapy/data`, and that data
-is still part of the base package. Do not migrate or delete it unless the task
-explicitly calls for a coordinated data migration.
-
-Use `ssapy.datadir` or `ssapy.utils.find_file()` when reading existing bundled
+SSAPy's data (ephemerides, gravity models, textures) comes from the required
+`llnl-ssapy-data` package, under its `ssapy/` tree; the repository no longer
+stores data or uses Git LFS. Planetary ephemerides are handled by `ssapy.ephemeris`:
+DE440 (`de440s.bsp`, 1849-2150) by default and a 1900-2150 DE430 excerpt on
+request. Epochs outside those spans download the full-span kernel from NAIF
+(checksummed, cached, with a warning); `SSAPY_EPHEMERIS_DOWNLOAD=0` disables
+that.
+
+Use `ssapy.datadir` or `ssapy.utils.find_file()` when reading bundled
 resources. Some model loaders already resolve packaged gravity, SPICE, and Earth
 orientation files internally; prefer those public loaders over hard-coded paths.
 
@@ -184,7 +188,7 @@ python -m twine check dist/*
 
 ## Common Pitfalls
 
-- Do not assume all packaged resources are small; base SSAPy still carries existing required data.
+- Do not add data files to this repository; add them to SSAPy-Data and release a new `llnl-ssapy-data`.
 - Do not add Git LFS as a default solution for new data in this repository.
 - Do not commit generated `_ssapy*.so`, `build/`, `dist/`, egg-info, docs build output, caches, or local environments.
 - Do not rely on unbuilt in-tree imports for code paths that require `ssapy._ssapy`.

ssapy/__init__.py

@@ -2,9 +2,23 @@
 
 __version__ = "1.1.10"
 
-datadir = os.path.join(os.path.dirname(__file__), "data")
+
+
+def _datadir():
+    """Directory holding SSAPy's data files: ssapy/ in llnl-ssapy-data."""
+    try:
+        from importlib.resources import files
+        return os.fspath(files("ssapy_data") / "data" / "ssapy")
+    except (ImportError, TypeError):
+        # llnl-ssapy-data is a required dependency; without it find_file
+        # raises a FileNotFoundError that says how to install it.
+        return os.path.join(os.path.dirname(__file__), "data")
+
+
+datadir = _datadir()
 
 from . import _ssapy
+from . import ephemeris  # noqa: F401  (ssapy.ephemeris.set_planetary_ephemeris)
 from .orbit import Orbit, EarthObserver, OrbitalObserver
 from .propagator import (
     KeplerianPropagator, SeriesPropagator, RK4Propagator, SGP4Propagator,

ssapy/accel.py

@@ -365,12 +365,14 @@ class AccelDrag(Accel):
     ----------
     recalc_threshold : float, optional
         Number of seconds past which the code will recompute the
-        precession/nutation matrix.  Default: 86400*30  (30 days)
+        precession/nutation matrix.  Default: 3600 (1 hour), matching
+        EarthOrientation; the previous 30-day default let the frame drift
+        5 arcsec.
     defaultkw : dict
         default parameters for kwargs passed to __call__,
         (area, mass, CR)
     """
-    def __init__(self, recalc_threshold=86400 * 30, **defaultkw):
+    def __init__(self, recalc_threshold=3600.0, **defaultkw):
         from . import _ssapy
 
         self.recalc_threshold = recalc_threshold
@@ -412,7 +414,10 @@ def __call__(self, r, v, t, _T=None, **kwargs):
                 self._t = t
                 self._T = erfa.pnm80(2400000.5, mjd_tt)
             _T = self._T
-        r_sun = sunPos(t)
+        # The density model works in the true-of-date frame, so the Sun's
+        # right ascension and declination must be of date too; sunPos is
+        # GCRF, which put the diurnal bulge 0.37 deg off in 2026.
+        r_sun = _T @ sunPos(t)
         r_tod = _T @ r
         v_tod = _T @ v
 
@@ -425,10 +430,9 @@ def __call__(self, r, v, t, _T=None, **kwargs):
             dec_sun
         )
         if not np.isfinite(density):
-            print(f"r_tod = {r_tod}")
-            print(f"ra_sun = {ra_sun}")
-            print(f"dec_sun = {dec_sun}")
-            raise ValueError("non finite density")
+            raise ValueError(
+                f"non finite density at r_tod = {r_tod}, ra_sun = {ra_sun}, dec_sun = {dec_sun}"
+            )
         a_tod = -0.5 * kw['CD'] * kw['area'] / kw['mass'] * density * v_rel * norm(v_rel)
         return _T.T @ a_tod