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static char help[] = "Model single-physics solver. Modified from ex19.c \n\\n";
/* ------------------------------------------------------------------------
See ex19.c for discussion of the problem
------------------------------------------------------------------------- */
#include "mp1.h"
extern PetscErrorCode FormInitialGuess(DMMG,Vec);
extern PetscErrorCode FormFunction(SNES,Vec,Vec,void*);
#undef __FUNCT__
#define __FUNCT__ "main"
int main(int argc,char **argv)
{
DMMG *dmmg; /* multilevel grid structure */
AppCtx user; /* user-defined work context */
PetscInt mx,my,its;
PetscErrorCode ierr;
MPI_Comm comm;
SNES snes;
DA da2;
PetscInitialize(&argc,&argv,(char *)0,help);
comm = PETSC_COMM_WORLD;
/* Problem parameters (velocity of lid, prandtl, and grashof numbers) */
ierr = PetscOptionsGetReal(PETSC_NULL,"-lidvelocity",&user.lidvelocity,PETSC_NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(PETSC_NULL,"-prandtl",&user.prandtl,PETSC_NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(PETSC_NULL,"-grashof",&user.grashof,PETSC_NULL);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create user context, set problem data, create vector data structures.
Also, compute the initial guess.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Setup Physics 2:
- Lap(T) + PR*Div([U*T,V*T]) = 0
where U and V are given by the given x.u and x.v
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DACreate2d(comm,DA_NONPERIODIC,DA_STENCIL_STAR,-4,-4,PETSC_DECIDE,PETSC_DECIDE,1,1,0,0,&da2);CHKERRQ(ierr);
ierr = DASetFieldName(da2,0,"temperature");CHKERRQ(ierr);
/* Create the solver object and attach the grid/physics info */
ierr = DMMGCreate(comm,1,&user,&dmmg);CHKERRQ(ierr);
ierr = DMMGSetDM(dmmg,(DM)da2);CHKERRQ(ierr);
ierr = DMMGSetISColoringType(dmmg,IS_COLORING_GLOBAL);CHKERRQ(ierr);
ierr = DMMGSetInitialGuess(dmmg,FormInitialGuess);CHKERRQ(ierr);
ierr = DMMGSetSNES(dmmg,FormFunction,0);CHKERRQ(ierr);
ierr = DMMGSetFromOptions(dmmg);CHKERRQ(ierr);
ierr = DAGetInfo(da2,PETSC_NULL,&mx,&my,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
user.lidvelocity = 1.0/(mx*my);
user.prandtl = 1.0;
user.grashof = 1.0;
/* Solve the nonlinear system */
ierr = DMMGSolve(dmmg);CHKERRQ(ierr);
snes = DMMGGetSNES(dmmg);
ierr = SNESGetIterationNumber(snes,&its);CHKERRQ(ierr);
ierr = PetscPrintf(comm,"Physics 2: Number of Newton iterations = %D\n\n", its);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Free spaces
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DADestroy(da2);CHKERRQ(ierr);
ierr = DMMGDestroy(dmmg);CHKERRQ(ierr);
ierr = PetscFinalize();CHKERRQ(ierr);
return 0;
}
#undef __FUNCT__
#define __FUNCT__ "FormInitialGuess"
PetscErrorCode FormInitialGuess(DMMG dmmg,Vec X)
{
PetscErrorCode ierr;
AppCtx *user = (AppCtx*)dmmg->user;
DA da2 = (DA)dmmg->dm;
Field2 **x2;
DALocalInfo info2;
PetscFunctionBegin;
/* Access the arrays inside of X */
ierr = DAVecGetArray(da2,X,(void**)&x2);CHKERRQ(ierr);
ierr = DAGetLocalInfo(da2,&info2);CHKERRQ(ierr);
/* Evaluate local user provided function */
ierr = FormInitialGuessLocal2(&info2,x2,user);CHKERRQ(ierr);
ierr = DAVecRestoreArray(da2,X,(void**)&x2);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
#undef __FUNCT__
#define __FUNCT__ "FormFunction"
PetscErrorCode FormFunction(SNES snes,Vec X,Vec F,void *ctx)
{
PetscErrorCode ierr;
DMMG dmmg = (DMMG)ctx;
AppCtx *user = (AppCtx*)dmmg->user;
DA da2 = (DA)dmmg->dm;
DALocalInfo info2;
Field2 **x2,**f2;
Vec X2;
PetscFunctionBegin;
ierr = DAGetLocalInfo(da2,&info2);CHKERRQ(ierr);
/* Get local vectors to hold ghosted parts of X */
ierr = DAGetLocalVector(da2,&X2);CHKERRQ(ierr);
ierr = DAGlobalToLocalBegin(da2,X,INSERT_VALUES,X2);CHKERRQ(ierr);
ierr = DAGlobalToLocalEnd(da2,X,INSERT_VALUES,X2);CHKERRQ(ierr);
/* Access the array inside of X1 */
ierr = DAVecGetArray(da2,X2,(void**)&x2);CHKERRQ(ierr);
/* Access the subvectors in F.
These are not ghosted so directly access the memory locations in F */
ierr = DAVecGetArray(da2,F,(void**)&f2);CHKERRQ(ierr);
/* Evaluate local user provided function */
ierr = FormFunctionLocal2(&info2,0,x2,f2,(void**)user);CHKERRQ(ierr);
ierr = DAVecRestoreArray(da2,F,(void**)&f2);CHKERRQ(ierr);
ierr = DAVecRestoreArray(da2,X2,(void**)&x2);CHKERRQ(ierr);
ierr = DARestoreLocalVector(da2,&X2);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
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