This DAE appears to be of index greater than 1.

Hi everyone! I'm trying to solve a PDE sys composed of 3 PDEs, using Partial Differential Equation Toolbox.

The error says that 'this DAE appears to be of index greater than 1.'

My codes can be downloaded from the link:

https://www.dropbox.com/sh/os4llwel9szwz45/AACbBLo-oSO0r5hu-9NWuiXaa?dl=0

The error displays:

'Error using daeic12 (line 76)

This DAE appears to be of index greater than 1.

Error in ode15s (line 302)

[y,yp,f0,dfdy,nFE,nPD,Jfac] = daeic12(odeFcn,odeArgs,t,ICtype,Mt,y,yp0,f0,...

Error in pde.EquationModel/solveTimeDependent (line 99)

sol=ode15s(fcn,tlist,uu0,odeoptions);

Error in pde.PDEModel/solvepde (line 57)

[u,dudt] = self.solveTimeDependent(coefstruct, u0, ut0, tlist, ...

Error in main_pde2 (line 42)

result = solvepde(model,tlist);'

Huge THANKS for your kind help.

Answer 1

[Kun Wang]

MATLAB experts, pls help me! Very confused! Need help!

Thank you all!