Analyzing and visualizing simulations

It is often necessary to analyze and visualize the output of a simulation to extract its scientific content. To this end, it is best to using libraries purposefully designed to work with the toolkit.


kuibit Visualization

Kuibit is a Python library to analyze and visualize simulations officially included in the Einstein Toolkit. The package reads simulation data and offers high-level intuitive interfaces to manipulate it.

The Einstein Toolkit comes with several kuibit scripts in Cactus/utils/Analysis/kuibit/examples, but the package has to be installed separately with pip. The included scripts can be used to make plots of grid functions, timeseries, gravitational waves, and other quantities. On the right, we show an example of a plot generated by one of these scripts,

Kuibit has its own documentation (which includes tutorials on how to use the package) and bug tracker.


VisIt Visualization Visit is a powerful general-purpose visualization tool based on the open source VTK library and is developed and maintained at the Lawrence Livermore National Laboratory. Visit can read HDF5 grid files output by the Einstein Toolkit and is especially suited for complex 3D plots. Visit offers a graphical user interface and can be scripted with Python. Some of the gallery examples contain Visit scripts, for example, GW150914.

Other tools

Kuibit and visit are not the only tools available to analyze simulations. The wiki entry on analysis and post-processing lists a few more (some of which may no longer be maintained but might have features not available in kuibit and visit). Moreover, the output of the Einstein Toolkit can be manipulated directly without using external libraries. For instance, a popular tool to quickly look at ASCII files is gnuplot.