YT: A Julia interface to yt

YT is a Julia interface to yt. yt is a Python package for the analysis and visualization of volumetric simulation data. For more information about yt, check out

What YT Does

YT exposes a number of the essential features of yt from within a Julia environment. These include:

  • Datasets
  • Data objects (e.g., spheres, rectangular regions, slices, projections, profiles, etc.)
  • Unit-aware quantities and arrays
  • Simple visualization tools (e.g., SlicePlot, ProjectionPlot, FixedResolutionBuffer)

YT enables the end-user to “ask” physically-motivated questions of volumetric data and work with the “answers” from within a Julia environment.

What YT Doesn’t Do (and Probably Won’t)

YT is not intended to be a full exposure of everything yt does. yt boasts many features, and exposing all of them would be somewhat redundant, especially those features that don’t involve a lot of additional coding on the part of the end-user. Some of these features include:

  • Analysis modules (e.g., particle trajectories, two-point functions, halo finders, simulated observations, etc.)
  • Initial conditions generation
  • Volume rendering
  • Utilities for cosmology, image writing, generating streamlines, clump finding, etc.

yt does a great job at handling these tasks already, and so if you are looking to use these features, working with yt directly from within a Python environment is the way to go. The purpose of YT is to expose the basic data loading and examining features of yt, as well as a few handy visualization tools, so that those who want to take advantage of the strengths of both Julia and yt strengths can do so.


This documentation does not exhaustively cover the API of the Python methods of yt that may be accessed via YT. For that, consulting the yt Documentation is recommended.

Current Version

The current stable version is 0.4.0. See the ChangeLog for details on changes from previous versions.

Indices and tables