Molass Library is a rewrite of MOLASS, a tool for the analysis of SEC-SAXS experiment data currently hosted at the Japanese synchrotron radiation facilities, Photon Factory and SPring-8
Tested Platforms
Continuous integration tests run on:
- Python 3.12, 3.13, 3.14 on Ubuntu (latest)
- Python 3.12, 3.13, 3.14 on Windows (latest)
Installation
Requirements: Python 3.12, 3.13, or 3.14
Linux (Ubuntu/Debian) prerequisites:
Before installing on Linux, ensure system build tools are available (needed to compile C extensions such as ultranest):
sudo apt install build-essential python3-dev
To install this package, use pip as follows:
pip install -U molass
pip install molass_data # Sample datasets for tutorials and testing
If your data lives in Dropbox, pip install molass[dropbox] adds an
API-based local cache (molass.DataUtils.sync_dropbox_folder) that avoids
the repeated re-downloads that can happen when reading directly from a
Dropbox-desktop-synced folder. See molass/DataUtils/DropboxSync.py for setup.
For development (requires molass-legacy as a sibling directory):
git clone https://github.com/biosaxs-dev/molass-library
git clone https://github.com/biosaxs-dev/molass-legacy
cd molass-library
pip install -e ".[testing]"
pip install molass_data
Quick Start
For a hands-on introduction, see the tutorial's Quick Start section, or run the corresponding test file:
pytest tests/tutorial/01-quick_start.py -v
Note: Running tests requires the development install. See CONTRIBUTING.md for setup instructions.
The molass-beginner repository provides an interactive onboarding experience in VS Code Agent mode.
Documentation
- Beginner Onboarding: https://github.com/biosaxs-dev/molass-beginner — Agent-mode first-run guide, for first-time users
- GUI: https://github.com/biosaxs-dev/molass-gui — Tkinter desktop app, for users who prefer a guided point-and-click workflow over notebooks
- Tutorial: https://biosaxs-dev.github.io/molass-tutorial — practical usage, for beginners
- Essence: https://biosaxs-dev.github.io/molass-essence — theory, for researchers
- Technical Report: https://biosaxs-dev.github.io/molass-technical — technical details, for advanced users
- Reference: https://biosaxs-dev.github.io/molass-library — function reference, for coding
- Legacy Repository: https://github.com/biosaxs-dev/molass-legacy — legacy code
Citation
If you use Molass Library in your research, please cite the JOSS paper:
Takahashi, M., & Shimizu, N. (2026). Molass Library: A Python Package for SEC-SAXS Data Analysis. Journal of Open Source Software, 11(124), 10403. https://doi.org/10.21105/joss.10403
@article{Takahashi2026,
doi = {10.21105/joss.10403},
url = {https://doi.org/10.21105/joss.10403},
year = {2026},
publisher = {The Open Journal},
volume = {11},
number = {124},
pages = {10403},
author = {Masatsuyo Takahashi and Nobutaka Shimizu},
title = {Molass Library: A Python Package for SEC-SAXS Data Analysis},
journal = {Journal of Open Source Software}
}
See also CITATION.cff for citing the software itself.
Community
To join the community, see:
- Handbook: https://biosaxs-dev.github.io/molass-develop — maintenance, for developers
- Contributing: CONTRIBUTING.md — how to contribute
- Support: GitHub Issues — questions, bugs, and feature requests
Especially for testing, see the first two sections in
Copilot Usage
Context is auto-loaded from .github/copilot-instructions.md when using GitHub Copilot in Agent mode (AI Context Standard).
For behavioral rules and user-type guidance, see Copilot/copilot-guidelines.md.
Optional Features
Excel reporting (Windows only):
If you want to use Excel reporting features (Windows only) for backward compatibility, install with the excel extra:
pip install -U molass[excel]
Note: The
excelextra installspywin32, which is required for Excel reporting and only works on Windows.
2 maintainers
Release files for molass 1.0.11
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Source distribution (sdist)
| File | Size | Uploaded | |
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| molass-1.0.11.tar.gz | 1.9 MB | Details |
Built distribution (wheel)
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|---|---|---|---|---|
| molass-1.0.11-py3-none-any.whl | Python 3 | none | any | Details |
Total release size: 3.0 MB
Release files / molass-1.0.11.tar.gz
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| Tags | Source |
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