Solve Differential Algebraic Equations (DAEs)

Hey

I have a problem whit solving DAE. I created them symbolically and followed the steps on:

https://ch.mathworks.com/help/symbolic/solve-differential-algebraic-equations.html

Although the function isLowIndexDAE(eqns,vars) returned 1 the ode15i solver gives an error message:

Error using daeic12 (line 76)

This DAE appears to be of index greater than 1.

Error in ode15s (line 310)

[y,yp,f0,dfdy,nFE,nPD,Jfac] =

daeic12(odeFcn,odeArgs,t,ICtype,Mt,y,yp0,f0,...

Error in symbolic_sim (line 158)

[tSol,ySol] = ode15s(daeFunctionNumericFF,[0

0.2],y0,opt);

Can somebody help me? The code is attached.

Regards

Answer 1

[Divya Yerraguntla]

Have a look at a similar question : https://www.mathworks.com/matlabcentral/answers/102944-what-is-the-meaning-of-this-dae-appears-to-be-of-index-greater-than-1-using-ode-solvers-for-solvin