petscmaster 20191020
TSSetRHSJacobian
Sets the function to compute the Jacobian of G, where U_t = G(U,t), as well as the location to store the matrix.
Synopsis
#include "petscts.h"
PetscErrorCode TSSetRHSJacobian(TS ts,Mat Amat,Mat Pmat,TSRHSJacobian f,void *ctx)
Logically Collective on TS
Input Parameters
 ts   the TS context obtained from TSCreate()

 Amat   (approximate) Jacobian matrix

 Pmat   matrix from which preconditioner is to be constructed (usually the same as Amat)

 f   the Jacobian evaluation routine

 ctx   [optional] userdefined context for private data for the
Jacobian evaluation routine (may be NULL)

Calling sequence of f
PetscErrorCode func (TS ts,PetscReal t,Vec u,Mat A,Mat B,void *ctx);
 t   current timestep

 u   input vector

 Amat   (approximate) Jacobian matrix

 Pmat   matrix from which preconditioner is to be constructed (usually the same as Amat)

 ctx   [optional] userdefined context for matrix evaluation routine

Notes
You must set all the diagonal entries of the matrices, if they are zero you must still set them with a zero value
The TS solver may modify the nonzero structure and the entries of the matrices Amat and Pmat between the calls to f()
You should not assume the values are the same in the next call to f() as you set them in the previous call.
See Also
SNESComputeJacobianDefaultColor(), TSSetRHSFunction(), TSRHSJacobianSetReuse(), TSSetIJacobian()
Level
beginner
Location
src/ts/interface/ts.c
Examples
src/ts/examples/tutorials/ex1.c.html
src/ts/examples/tutorials/ex2.c.html
src/ts/examples/tutorials/ex3.c.html
src/ts/examples/tutorials/ex4.c.html
src/ts/examples/tutorials/ex5.c.html
src/ts/examples/tutorials/ex6.c.html
src/ts/examples/tutorials/ex13.c.html
src/ts/examples/tutorials/ex21.c.html
src/ts/examples/tutorials/ex31.c.html
src/ts/examples/tutorials/extchem.c.html
src/ts/examples/tutorials/ex20adj.c.html
Index of all TS routines
Table of Contents for all manual pages
Index of all manual pages