You are looking at the documentation for pynbody v2, which is currently in beta. To install pynbody v2 beta, use pip install --pre pynbody. Documentation for v1 remains available at https://pynbody.github.io/pynbody/ .

Welcome to the documentation for pynbody – an analysis package for astrophysical N-body and Smooth Particle Hydrodynamics simulations, supporting Python 3 with minor version support adhering roughly to the SPEC0 policy.

Installation should be as simple as

pip install pynbody

but if you run into trouble, try the Pynbody Installation guide.

Once installed, we recommend you get started by trying the Pynbody Tutorials.


Pynbody is a complex project maintained by a small team of scientists, and our dayjobs is doing science! We do our best to provide support, and we greatly appreciate feedback and bug reports. If you encounter any problems, please consider opening an issue on github or posting to our email list. To help us help you, when asking for assistance please provide a simple, minimal python script that we can use to reproduce a bug, inaccuracy or situation. Preferably reproduce the bug using pynbody’s own test data (as used by the tutorials, and downloadable at http://star.ucl.ac.uk/~app/testdata.tar.gz). If this impossible, provide us a pointer to another file that we can use to reproduce the problem.

Please note that we adhere to a community code of conduct, which you should read and understand before posting to the users list or in a github issue.

Open science relies on good will and reciprocity. Please strongly consider contributing any enhancements or fixes of your own back to the project using a pull request.

Acknowledging Pynbody in Scientific Publications#

Pynbody development is an open-source, community effort.We ask that if you use pynbody in preparing a scientific publication, you cite it via its Astrophysics Source Code Library entry using the following BibTex:

  author = {{Pontzen}, A. and {Ro{\v s}kar}, R. and {Stinson}, G.~S. and {Woods},
     R. and {Reed}, D.~M. and {Coles}, J. and {Quinn}, T.~R.},
  title = "{pynbody: Astrophysics Simulation Analysis for Python}",
  note = {Astrophysics Source Code Library, ascl:1305.002},
  year = 2013

Where next?#

Consult the Pynbody Installation documentation for instructions on how to get going. Then you might like to download some test data and try out the quick-start tutorial which gets straight to some of pynbody’s analysis features. Or, if you prefer to learn a little more of how your data is organized, we also provide a data access walkthrough.

Our full documentation is organized into three sections: