★★★ GReTA Special Event ★★★ Compositional Modeling with Decorated Cospans


Decorated cospans are a general framework for composing open networks and mapping them to dynamical systems. We explain this framework and illustrate it with the example of stock and flow diagrams. These diagrams are widely used in epidemiology to model the dynamics of populations. Although tools already exist for building these diagrams and simulating the systems they describe, we have created a new software package called StockFlow which uses decorated cospans to overcome some limitations of existing software. Our approach cleanly separates the syntax of stock and flow diagrams from the semantics they can be assigned. We have implemented a semantics where stock and flow diagrams are mapped to ordinary differential equations, although others are possible. We illustrate this with code in StockFlow that implements a simplified version of a COVID-19 model used in Canada. This is joint work with Xiaoyan Li, Sophie Libkind, Nathaniel Osgood and Evan Patterson.

Wednesday, June 29, 2022 19:00 Europe/Paris
GReTA seminar
Zoom registration: click here! Please consider joining the meeting already within the 15min prior to the start of the seminar to ensure your setup is functioning properly. You may connect with either the Zoom web or Zoom desktop clients.

Please note that the meeting will be recorded and live-streamed to YouTube:

John Baez
John Baez

I’m a mathematical physicist. I work at the math department at U. C. Riverside in California, and also at the Centre for Quantum Technologies in Singapore and the Topos Institute in Berkeley.
Among other things, I study networks and help researchers use them in scientific computation, such as quickly adaptable models of infectious disease.