Further Inquiry Regarding MatCont Error and Additional Equation

[李冉冉]

Hi there!
I hope this message finds you well. I am currently working on a dynamic systems analysis using MatCont, and I encountered an error that I'm seeking assistance with.

The error message I received is: "Equations are in the wrong order, compared to the coordinates." Based on my understanding, this suggests a mismatch between the order of the equations and the order of the coordinates or parameters. I have reviewed my input file and made adjustments, but the issue persists.

I am attaching the modified version of the system at Attachment with pic.Could you please tell me specifically where the error is?

Is it reasonable to add the equation dz/dt=... in this manner to represent the target function like 1/2⋅(py1+in1)?

I appreciate your expertise and guidance on this matter.

Thank you for your time and assistance.

[hilmeijer]

Two things to improve for defining your system
1. Yes, you can use expressions, but these have to come before the differential equations.
2. Do not use indexed arrays or functions, so change g4(re2)=2.8re2+0.5 to g4=2.8re2+0.5, and then use g4 and alike in your equations.
Good luck.

[李冉冉]

I hope this message finds you well. I greatly appreciate your prompt response and valuable guidance on the system definition.

Following your suggestions, I have made modifications to the equations, ensuring that expressions precede the differential equations. However, despite these changes, I still encounter the same error as before. It's possible that I may have misunderstood your instructions.

Could you please provide additional guidance or clarification on the modifications? I am eager to learn and would greatly appreciate any further assistance you can provide.

[hilmeijer]

A few more comments:
1. Write py1' (with apostrophe) to declare an ODE
2. If z is a coordinate, then provide an ODE for it.
3. The expressions f1...f7 and g1...g4 should be put before the ODEs.
4. The factor 100000 will later make continuation difficult; you can probably relax this to 100 or 10 and get similar results.

[李冉冉]

Thanks to your guidance, my system is now running successfully.