.. _chapter:Catalyst: Catalyst ======== Catalyst is an **in situ framework** created as part of ParaView a few years ago. Also known as coprocessing or concurrent analysis, the in situ workflow allows you to perform **analysis and visualization** at the time of the simulation. As only the output of the analysis is written on the disk, the **I/O** operations are **considerably reduced** compared to: - writing full simulation output - reading the full-size data in an analysis tool - writing the analysis output. ParaView Catalyst provides a small, easy-to-use, API that any simulation developed in C++, C, Fortran or Python can use to do in situ analysis without developing its own custom data analysis code. Simply give it a ParaView Python pipeline and your input data! .. toctree:: :maxdepth: 2 introduction getting_started background blueprints fides examples debugging