Chaotic behavior: Modelica.Electrical.Analog.Examples.ChuaCircuit

[AHaumer]

I wonder whether the results of the above mentioned example can be compared between different simulators. The default parameter settings lead to chaotic behavior. The results are extremely sensitive not only to parameters and initial conditions but also to tolerance and details of the solver. Choosing other parameter settings would either lead to periodic behavior or to a fix point. The parameters are extremely unrealistic and can't be validated with a real circuit: Who can get an inductance of 18 H and capacitances of 100 F and 10 F? @casella mentioned another chaotic oscillator in another discussion (#4771). Inspired by that, I implemented a few chaotic circuits with realistic parameters. They are even of didactic interest, I wonder whether we should:

• Just newly parameterize the mentioned example to obtain periodic behavior, and mention in the documentation how to get chaos.
• Add my examples to Modelica.Electrical.Analog.Examples with parameters for periodic behavior and describe how to get chaos.

I'm pretty sure that examples with chaotic behavior are nice demos but a very bad base for comparing results between different tools. @casella @HansOlsson @christiankral What's your opinion?