sum_stat

Python wrapper package for measuring cosmological summary statistics from galaxy catalogues and lensing data. Careful, this is an early version, use at own risk !

Estimators

Stable — production-ready, covered by shape, consistency, and analytic-recovery tests:

• Luminosity and stellar mass functions (1/V_max, SWML, C⁻, STY, Efron–Petrosian τ, Rauzy)
• Angular correlation function w(θ)
• Projected correlation function w_p(r_p), ξ(r), ξ_ℓ(s)
• Excess surface density ΔΣ (galaxy-galaxy lensing)

In development — APIs may change, not yet validated for science; see development_estimators:

• Thermal SZ: stacked galaxy × Compton-y Σ_y(r_p) and compensated aperture photometry T_AP(θ_d) on ACT DR6 maps
• Power spectra C_ℓ, P_ℓ(k)
• k-nearest-neighbour CDFs
• Redshift distributions n(z)

All estimators write self-documenting HDF5 with units and cosmology provenance.

Installation

pip install sum-stat

Some estimators need optional extras:

pip install 'sum-stat[sz]'        # pixell — thermal SZ on CAR maps
pip install 'sum-stat[lensing]'   # dsigma — ΔΣ pipeline
pip install 'sum-stat[knn]'       # pyfnntw — kNN backend (needs a Rust toolchain)
pip install 'sum-stat[scripts]'   # matplotlib, tqdm — the scripts/ pipeline and plots

See pypi.org/project/sum-stat for details, and the documentation for the user guide and API reference.

Citation

If you use sum_stat in your research, please cite it as:

@software{comparat2026sumstat,
  author  = {Comparat, Johan},
  title   = {{sum\_stat}: Cosmological summary statistics from galaxy catalogues and lensing data}, 
  year    = {2026},
  version = {0.4.0},
  url     = {https://github.com/JohanComparat/sum_stat},
  license = {MIT},
}

A CITATION.cff file is also provided for automated citation tools (GitHub "Cite this repository" button).

Contributing

Contributions are welcome! Please read CONTRIBUTING.md for development setup, coding conventions, and how to submit a pull request.

License

MIT — see LICENSE.

Package structure

sum_stat/
├── sum_stat/
│   ├── catalogue.py       # GalaxyCatalogue, ShapeCatalogue, PhotoZCalibTable
│   ├── cosmology.py       # JAX-differentiable distances and Σ_crit
│   ├── covariance/        # jackknife_covariance, bootstrap_covariance
│   ├── io/                # SummaryStatWriter, SummaryStatReader
│   ├── lensing/           # delta_sigma
│   ├── lf_smf/            # 1/Vmax, SWML, C⁻, STY, EP τ, Rauzy
│   ├── twopcf/            # w_theta, wp, xi_r, xi_multipoles
│   ├── sz/                # stacked_y, stacked_cap, binning  [development]
│   ├── knn/               # knn_cdf, cross_knn_cdf          [development]
│   ├── nz/                # nz_histogram, nz_kde            [development]
│   └── powspec/           # cl_angular, pk3d, pk_multipoles [development]
├── tests/
├── docs/
├── environment.yml
└── pyproject.toml