TSComputeIJacobianConstant#
Reuses the matrix previously computed with the provided TSIJacobianFn for a semi-implicit DAE or ODE
Synopsis#
#include "petscts.h"  
PetscErrorCode TSComputeIJacobianConstant(TS ts, PetscReal t, Vec U, Vec Udot, PetscReal shift, Mat A, Mat B, void *ctx)
Collective
Input Parameters#
- ts - time stepping context 
- t - time at which to evaluate 
- U - state at which to evaluate 
- Udot - time derivative of state vector 
- shift - shift to apply 
- ctx - context 
Output Parameters#
- A - pointer to operator 
- B - pointer to matrix from which the preconditioner is built (often - A)
Notes#
This function is intended to be passed to TSSetIJacobian() to evaluate the Jacobian for linear time-independent problems.
It is only appropriate for problems of the form
where M is constant and F is non-stiff.  The user must pass M to TSSetIJacobian().  The current implementation only
works with IMEX time integration methods such as TSROSW and TSARKIMEX, since there is no support for de-constructing
an implicit operator of the form
where J is the Jacobian of -F(U). Support may be added in a future version of PETSc, but for now, the user must store a copy of M or reassemble it when requested.
See Also#
TS: Scalable ODE and DAE Solvers, TS, TSROSW, TSARKIMEX, TSSetIFunction(), TSSetIJacobian(), TSComputeIFunctionLinear()
Level#
advanced
Location#
Index of all TS routines
Table of Contents for all manual pages
Index of all manual pages