int main(int argc,char **argv)
{
AppCtx appctx; /* user-defined application context */
PetscErrorCode ierr;
PetscInt i, xs, xm, ind, j, lenglob;
PetscReal x, *wrk_ptr1, *wrk_ptr2;
MatNullSpace nsp;
PetscMPIInt size;
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Initialize program and set problem parameters
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
PetscFunctionBegin;
ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
/*initialize parameters */
appctx.param.N = 10; /* order of the spectral element */
appctx.param.E = 10; /* number of elements */
appctx.param.L = 4.0; /* length of the domain */
appctx.param.mu = 0.01; /* diffusion coefficient */
appctx.initial_dt = 5e-3;
appctx.param.steps = PETSC_MAX_INT;
appctx.param.Tend = 4;
ierr = PetscOptionsGetInt(NULL,NULL,"-N",&appctx.param.N,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetInt(NULL,NULL,"-E",&appctx.param.E,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(NULL,NULL,"-Tend",&appctx.param.Tend,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(NULL,NULL,"-mu",&appctx.param.mu,NULL);CHKERRQ(ierr);
appctx.param.Le = appctx.param.L/appctx.param.E;
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
if (appctx.param.E % size) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_ARG_WRONG,"Number of elements must be divisible by number of processes");
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create GLL data structures
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = PetscGLLCreate(appctx.param.N,PETSCGLL_VIA_LINEARALGEBRA,&appctx.SEMop.gll);CHKERRQ(ierr);
lenglob = appctx.param.E*(appctx.param.N-1);
/*
Create distributed array (DMDA) to manage parallel grid and vectors
and to set up the ghost point communication pattern. There are E*(Nl-1)+1
total grid values spread equally among all the processors, except first and last
*/
ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_PERIODIC,lenglob,1,1,NULL,&appctx.da);CHKERRQ(ierr);
ierr = DMSetFromOptions(appctx.da);CHKERRQ(ierr);
ierr = DMSetUp(appctx.da);CHKERRQ(ierr);
/*
Extract global and local vectors from DMDA; we use these to store the
approximate solution. Then duplicate these for remaining vectors that
have the same types.
*/
ierr = DMCreateGlobalVector(appctx.da,&appctx.dat.curr_sol);CHKERRQ(ierr);
ierr = VecDuplicate(appctx.dat.curr_sol,&appctx.SEMop.grid);CHKERRQ(ierr);
ierr = VecDuplicate(appctx.dat.curr_sol,&appctx.SEMop.mass);CHKERRQ(ierr);
ierr = DMDAGetCorners(appctx.da,&xs,NULL,NULL,&xm,NULL,NULL);CHKERRQ(ierr);
ierr = DMDAVecGetArray(appctx.da,appctx.SEMop.grid,&wrk_ptr1);CHKERRQ(ierr);
ierr = DMDAVecGetArray(appctx.da,appctx.SEMop.mass,&wrk_ptr2);CHKERRQ(ierr);
/* Compute function over the locally owned part of the grid */
xs=xs/(appctx.param.N-1);
xm=xm/(appctx.param.N-1);
/*
Build total grid and mass over entire mesh (multi-elemental)
*/
for (i=xs; i<xs+xm; i++) {
for (j=0; j<appctx.param.N-1; j++) {
x = (appctx.param.Le/2.0)*(appctx.SEMop.gll.nodes[j]+1.0)+appctx.param.Le*i;
ind=i*(appctx.param.N-1)+j;
wrk_ptr1[ind]=x;
wrk_ptr2[ind]=.5*appctx.param.Le*appctx.SEMop.gll.weights[j];
if (j==0) wrk_ptr2[ind]+=.5*appctx.param.Le*appctx.SEMop.gll.weights[j];
}
}
ierr = DMDAVecRestoreArray(appctx.da,appctx.SEMop.grid,&wrk_ptr1);CHKERRQ(ierr);
ierr = DMDAVecRestoreArray(appctx.da,appctx.SEMop.mass,&wrk_ptr2);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create matrix data structure; set matrix evaluation routine.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DMSetMatrixPreallocateOnly(appctx.da, PETSC_TRUE);CHKERRQ(ierr);
ierr = DMCreateMatrix(appctx.da,&appctx.SEMop.stiff);CHKERRQ(ierr);
ierr = DMCreateMatrix(appctx.da,&appctx.SEMop.grad);CHKERRQ(ierr);
/*
For linear problems with a time-dependent f(u,t) in the equation
u_t = f(u,t), the user provides the discretized right-hand-side
as a time-dependent matrix.
*/
ierr = RHSMatrixLaplaciangllDM(appctx.ts,0.0,appctx.dat.curr_sol,appctx.SEMop.stiff,appctx.SEMop.stiff,&appctx);CHKERRQ(ierr);
ierr = RHSMatrixAdvectiongllDM(appctx.ts,0.0,appctx.dat.curr_sol,appctx.SEMop.grad,appctx.SEMop.grad,&appctx);CHKERRQ(ierr);
/*
For linear problems with a time-dependent f(u,t) in the equation
u_t = f(u,t), the user provides the discretized right-hand-side
as a time-dependent matrix.
*/
ierr = MatDuplicate(appctx.SEMop.stiff,MAT_COPY_VALUES,&appctx.SEMop.keptstiff);CHKERRQ(ierr);
/* attach the null space to the matrix, this probably is not needed but does no harm */
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nsp);CHKERRQ(ierr);
ierr = MatSetNullSpace(appctx.SEMop.stiff,nsp);CHKERRQ(ierr);
ierr = MatSetNullSpace(appctx.SEMop.keptstiff,nsp);CHKERRQ(ierr);
ierr = MatNullSpaceTest(nsp,appctx.SEMop.stiff,NULL);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr);
/* attach the null space to the matrix, this probably is not needed but does no harm */
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nsp);CHKERRQ(ierr);
ierr = MatSetNullSpace(appctx.SEMop.grad,nsp);CHKERRQ(ierr);
ierr = MatNullSpaceTest(nsp,appctx.SEMop.grad,NULL);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr);
/* Create the TS solver that solves the ODE and its adjoint; set its options */
ierr = TSCreate(PETSC_COMM_WORLD,&appctx.ts);CHKERRQ(ierr);
ierr = TSSetProblemType(appctx.ts,TS_NONLINEAR);CHKERRQ(ierr);
ierr = TSSetType(appctx.ts,TSRK);CHKERRQ(ierr);
ierr = TSSetDM(appctx.ts,appctx.da);CHKERRQ(ierr);
ierr = TSSetTime(appctx.ts,0.0);CHKERRQ(ierr);
ierr = TSSetTimeStep(appctx.ts,appctx.initial_dt);CHKERRQ(ierr);
ierr = TSSetMaxSteps(appctx.ts,appctx.param.steps);CHKERRQ(ierr);
ierr = TSSetMaxTime(appctx.ts,appctx.param.Tend);CHKERRQ(ierr);
ierr = TSSetExactFinalTime(appctx.ts,TS_EXACTFINALTIME_MATCHSTEP);CHKERRQ(ierr);
ierr = TSSetTolerances(appctx.ts,1e-7,NULL,1e-7,NULL);CHKERRQ(ierr);
ierr = TSSetSaveTrajectory(appctx.ts);CHKERRQ(ierr);
ierr = TSSetFromOptions(appctx.ts);CHKERRQ(ierr);
ierr = TSSetRHSFunction(appctx.ts,NULL,RHSFunction,&appctx);CHKERRQ(ierr);
ierr = TSSetRHSJacobian(appctx.ts,appctx.SEMop.stiff,appctx.SEMop.stiff,RHSJacobian,&appctx);CHKERRQ(ierr);
/* Set Initial conditions for the problem */
ierr = TrueSolution(appctx.ts,0,appctx.dat.curr_sol,&appctx);CHKERRQ(ierr);
ierr = TSSetSolutionFunction(appctx.ts,(PetscErrorCode (*)(TS,PetscReal,Vec,void *))TrueSolution,&appctx);CHKERRQ(ierr);
ierr = TSSetTime(appctx.ts,0.0);CHKERRQ(ierr);
ierr = TSSetStepNumber(appctx.ts,0);CHKERRQ(ierr);
ierr = TSSolve(appctx.ts,appctx.dat.curr_sol);CHKERRQ(ierr);
ierr = MatDestroy(&appctx.SEMop.stiff);CHKERRQ(ierr);
ierr = MatDestroy(&appctx.SEMop.keptstiff);CHKERRQ(ierr);
ierr = MatDestroy(&appctx.SEMop.grad);CHKERRQ(ierr);
ierr = VecDestroy(&appctx.SEMop.grid);CHKERRQ(ierr);
ierr = VecDestroy(&appctx.SEMop.mass);CHKERRQ(ierr);
ierr = VecDestroy(&appctx.dat.curr_sol);CHKERRQ(ierr);
ierr = PetscGLLDestroy(&appctx.SEMop.gll);CHKERRQ(ierr);
ierr = DMDestroy(&appctx.da);CHKERRQ(ierr);
ierr = TSDestroy(&appctx.ts);CHKERRQ(ierr);
/*
Always call PetscFinalize() before exiting a program. This routine
- finalizes the PETSc libraries as well as MPI
- provides summary and diagnostic information if certain runtime
options are chosen (e.g., -log_summary).
*/
ierr = PetscFinalize();
return ierr;
}
int Brusselator(int argc,char **argv,PetscInt cycle)
{
TS ts; /* nonlinear solver */
Vec X; /* solution, residual vectors */
Mat J; /* Jacobian matrix */
PetscInt steps,maxsteps,mx;
PetscErrorCode ierr;
DM da;
PetscReal ftime,hx,dt,xmax,xmin;
struct _User user; /* user-defined work context */
TSConvergedReason reason;
PetscInitialize(&argc,&argv,(char*)0,help);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create distributed array (DMDA) to manage parallel grid and vectors
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_NONE,-11,2,2,NULL,&da);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Extract global vectors from DMDA;
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DMCreateGlobalVector(da,&X);CHKERRQ(ierr);
/* Initialize user application context */
ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Advection-reaction options","");
{
user.A = 1;
user.B = 3;
user.alpha = 0.1;
user.uleft = 1;
user.uright = 1;
user.vleft = 3;
user.vright = 3;
ierr = PetscOptionsReal("-A","Reaction rate","",user.A,&user.A,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-B","Reaction rate","",user.B,&user.B,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-alpha","Diffusion coefficient","",user.alpha,&user.alpha,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-uleft","Dirichlet boundary condition","",user.uleft,&user.uleft,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-uright","Dirichlet boundary condition","",user.uright,&user.uright,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-vleft","Dirichlet boundary condition","",user.vleft,&user.vleft,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-vright","Dirichlet boundary condition","",user.vright,&user.vright,NULL);CHKERRQ(ierr);
}
ierr = PetscOptionsEnd();CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create timestepping solver context
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr);
ierr = TSSetDM(ts,da);CHKERRQ(ierr);
ierr = TSSetType(ts,TSARKIMEX);CHKERRQ(ierr);
ierr = TSSetRHSFunction(ts,NULL,FormRHSFunction,&user);CHKERRQ(ierr);
ierr = TSSetIFunction(ts,NULL,FormIFunction,&user);CHKERRQ(ierr);
ierr = DMSetMatType(da,MATAIJ);CHKERRQ(ierr);
ierr = DMCreateMatrix(da,&J);CHKERRQ(ierr);
ierr = TSSetIJacobian(ts,J,J,FormIJacobian,&user);CHKERRQ(ierr);
ftime = 1.0;
maxsteps = 10000;
ierr = TSSetDuration(ts,maxsteps,ftime);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Set initial conditions
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = FormInitialSolution(ts,X,&user);CHKERRQ(ierr);
ierr = TSSetSolution(ts,X);CHKERRQ(ierr);
ierr = VecGetSize(X,&mx);CHKERRQ(ierr);
hx = 1.0/(PetscReal)(mx/2-1);
dt = 0.4 * PetscSqr(hx) / user.alpha; /* Diffusive stability limit */
dt *= PetscPowRealInt(0.2,cycle); /* Shrink the time step in convergence study. */
ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr);
ierr = TSSetTolerances(ts,1e-3*PetscPowRealInt(0.5,cycle),NULL,1e-3*PetscPowRealInt(0.5,cycle),NULL);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Set runtime options
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Solve nonlinear system
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSSolve(ts,X);CHKERRQ(ierr);
ierr = TSGetSolveTime(ts,&ftime);CHKERRQ(ierr);
ierr = TSGetTimeStepNumber(ts,&steps);CHKERRQ(ierr);
ierr = TSGetConvergedReason(ts,&reason);CHKERRQ(ierr);
ierr = VecMin(X,NULL,&xmin);CHKERRQ(ierr);
ierr = VecMax(X,NULL,&xmax);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"%s at time %g after % 3D steps. Range [%6.4f,%6.4f]\n",TSConvergedReasons[reason],(double)ftime,steps,(double)xmin,(double)xmax);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Free work space.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = MatDestroy(&J);CHKERRQ(ierr);
ierr = VecDestroy(&X);CHKERRQ(ierr);
ierr = TSDestroy(&ts);CHKERRQ(ierr);
ierr = DMDestroy(&da);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
/*
FormFunctionGradient - Evaluates the function and corresponding gradient.
Input Parameters:
tao - the Tao context
X - the input vector
ptr - optional user-defined context, as set by TaoSetObjectiveAndGradientRoutine()
Output Parameters:
f - the newly evaluated function
G - the newly evaluated gradient
*/
PetscErrorCode FormFunctionGradient(Tao tao,Vec IC,PetscReal *f,Vec G,void *ctx)
{
User user = (User)ctx;
TS ts;
PetscScalar *x_ptr,*y_ptr;
PetscErrorCode ierr;
PetscScalar *ic_ptr;
ierr = VecCopy(IC,user->x);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create timestepping solver context
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr);
ierr = TSSetType(ts,TSRK);CHKERRQ(ierr);
ierr = TSSetRHSFunction(ts,NULL,RHSFunction,user);CHKERRQ(ierr);
ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Set time
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSSetTime(ts,0.0);CHKERRQ(ierr);
ierr = TSSetInitialTimeStep(ts,0.0,.001);CHKERRQ(ierr);
ierr = TSSetDuration(ts,2000,0.5);CHKERRQ(ierr);
ierr = TSSetTolerances(ts,1e-7,NULL,1e-7,NULL);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Save trajectory of solution so that TSAdjointSolve() may be used
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSSetSaveTrajectory(ts);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Set runtime options
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
ierr = TSSolve(ts,user->x);CHKERRQ(ierr);
ierr = TSGetSolveTime(ts,&user->ftime);CHKERRQ(ierr);
ierr = TSGetTimeStepNumber(ts,&user->steps);CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"mu %.6f, steps %D, ftime %g\n",(double)user->mu,user->steps,(double)user->ftime);CHKERRQ(ierr);
ierr = VecGetArray(IC,&ic_ptr);CHKERRQ(ierr);
ierr = VecGetArray(user->x,&x_ptr);CHKERRQ(ierr);
*f = (x_ptr[0]-user->x_ob[0])*(x_ptr[0]-user->x_ob[0])+(x_ptr[1]-user->x_ob[1])*(x_ptr[1]-user->x_ob[1]);
ierr = PetscPrintf(PETSC_COMM_WORLD,"Observed value y_ob=[%f; %f], ODE solution y=[%f;%f], Cost function f=%f\n",(double)user->x_ob[0],(double)user->x_ob[1],(double)x_ptr[0],(double)x_ptr[1],(double)(*f));CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Adjoint model starts here
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* Redet initial conditions for the adjoint integration */
ierr = VecGetArray(user->lambda[0],&y_ptr);CHKERRQ(ierr);
y_ptr[0] = 2.*(x_ptr[0]-user->x_ob[0]);
y_ptr[1] = 2.*(x_ptr[1]-user->x_ob[1]);
ierr = VecRestoreArray(user->lambda[0],&y_ptr);CHKERRQ(ierr);
ierr = TSSetCostGradients(ts,1,user->lambda,NULL);CHKERRQ(ierr);
/* Set RHS Jacobian for the adjoint integration */
ierr = TSSetRHSJacobian(ts,user->A,user->A,RHSJacobian,user);CHKERRQ(ierr);
ierr = TSAdjointSolve(ts);CHKERRQ(ierr);
ierr = VecCopy(user->lambda[0],G);
ierr = TSDestroy(&ts);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
void PETSC_STDCALL tssettolerances_(TS ts,PetscReal *atol,Vec vatol,PetscReal *rtol,Vec vrtol, int *__ierr ){
*__ierr = TSSetTolerances(
(TS)PetscToPointer((ts) ),*atol,
(Vec)PetscToPointer((vatol) ),*rtol,
(Vec)PetscToPointer((vrtol) ));
}
