[petsc-users] is TS_EQ_DAE_SEMI_EXPLICIT_INDEX functional

[Zhang, Hong]

You do not need to worry about these equation flags in the beginning. To solve a DAE, you need to define IFunction and IJacobian instead of RHSFunction. ts/examples/tutorials/ex19.c is the simplest DAE example that you can refer to.

Hong (Mr.)

> On Sep 2, 2019, at 4:51 AM, Huck, Moritz via petsc-users <petsc-users at mcs.anl.gov> wrote:
> 
> Hi,
> TS_EQ_DAE_SEMI_EXPLICIT_INDEX(?) are defined in TSEquationType but not mentioned in the manual.
> Is this feature functional ?
> If yes how do I have to define the RHSFunction? 
> (I am asking since the ODE variant has it defined as G= M^-1 g, which cannot work for a DAE)
> 
> Best Regards,
> Moritz