Welcome to ytree.

ytree is a tool for working with merger tree data from multiple sources. ytree is an extension of the yt analysis toolkit and provides a similar interface for merger tree data that includes universal field names, derived fields, symbolic units, parallel functionality, and a framework for performing complex analysis. ytree is able to load in merger tree from the following formats:

See Loading Data for instructions specific to each format. All formats can be resaved with a universal format that can be reloaded with ytree. Individual trees for single halos can also be saved.

I want to make merger trees!

If you have halo catalog data that can be loaded by yt, then you can use the treefarm package to create merger trees. treefarm was once a part of ytree, but is now its own thing.

Citing ytree

If you use ytree in your work, please cite the following:

Smith et al., (2019). ytree: A Python package for analyzing merger trees. Journal of Open Source Software, 4(44), 1881, https://doi.org/10.21105/joss.01881

For BibTeX users:

  doi = {10.21105/joss.01881},
  url = {https://doi.org/10.21105/joss.01881},
  year  = {2019},
  month = {dec},
  publisher = {The Open Journal},
  volume = {4},
  number = {44},
  pages = {1881},
  author = {Britton D. Smith and Meagan Lang},
  title = {ytree: A Python package for analyzing merger trees},
  journal = {Journal of Open Source Software}

If you would like to also cite the specific version of ytree used in your work, include the following reference:

  author       = {Britton Smith and
                  Meagan Lang and
                  Juanjo Bazán},
  title        = {ytree-project/ytree: ytree 3.2.0 Release},
  month        = nov,
  year         = 2022,
  publisher    = {Zenodo},
  version      = {ytree-3.2.0},
  doi          = {10.5281/zenodo.7335683},
  url          = {https://doi.org/10.5281/zenodo.7335683}