What is a "system variable" in a Simulink model?

Hi, I am reading documentation regarding how to use solvers for Simscape, and I ran across the term "system variable" in the following page:

https://www.mathworks.com/help/physmod/simscape/ug/how-simscape-models-represent-physical-systems.html

Any ideas on what specifically is a "system variable?"

My inclination is to think it's likely the time of a simulation, or rather the input to the system (and how that relates to time). I don't know if that's correct though.

Thank you,

Theo

Answer 1

[Jim Riggs]

In this context, the "system" is the device that you are modelling. Therefore, a "system variable" is one of the variables in your model. It appears that, in the referenced link, the "system" is specifically a reference to the equations of state, so "system variables" are the state variables in the model equations.