TSComputeIJacobianDefaultColor#
Computes the Jacobian using finite differences and coloring to exploit matrix sparsity.
Synopsis#
#include "petscts.h"  
PetscErrorCode TSComputeIJacobianDefaultColor(TS ts, PetscReal t, Vec U, Vec Udot, PetscReal shift, Mat J, Mat B, void *ctx)
Collective
Input Parameters#
- ts - the - TScontext
- t - current timestep 
- U - state vector 
- Udot - time derivative of state vector 
- shift - shift to apply, see note below 
- ctx - an optional user context 
Output Parameters#
- J - Jacobian matrix (not altered in this routine) 
- B - newly computed Jacobian matrix to use with preconditioner (generally the same as - J)
Notes#
If F(t,U,Udot)=0 is the DAE, the required Jacobian is
dF/dU + shift*dF/dUdot
Most users should not need to explicitly call this routine, as it is used internally within the nonlinear solvers.
This will first try to get the coloring from the DM.  If the DM type has no coloring
routine, then it will try to get the coloring from the matrix.  This requires that the
matrix have nonzero entries precomputed.
See Also#
TS: Scalable ODE and DAE Solvers, TS, TSSetIJacobian(), MatFDColoringCreate(), MatFDColoringSetFunction()
Level#
intermediate
Location#
Index of all TS routines
Table of Contents for all manual pages
Index of all manual pages