petsc-3.14.6 2021-03-30

TSComputeIFunction

Evaluates the DAE residual written in implicit form F(t,U,Udot)=0

#include "petscts.h"  
PetscErrorCode TSComputeIFunction(TS ts,PetscReal t,Vec U,Vec Udot,Vec Y,PetscBool imex)

Collective on TS

	ts	- the TS context
	t	- current time
	U	- state vector
	Udot	- time derivative of state vector
	imex	- flag indicates if the method is IMEX so that the RHSFunction should be kept separate

- right hand side

Most users should not need to explicitly call this routine, as it is used internally within the nonlinear solvers.

If the user did did not write their equations in implicit form, this function recasts them in implicit form.

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