int main(int argc, char **argv) { TS ts; Vec x; /*solution vector*/ Mat A; /*Jacobian*/ PetscInt steps,maxsteps,mx; PetscErrorCode ierr; PetscReal ftime; AppCtx user; /* user-defined work context */ PetscInitialize(&argc,&argv,NULL,help); /* Initialize user application context */ ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Allen-Cahn equation",""); user.param = 9e-4; user.xleft = -1.; user.xright = 2.; user.mx = 400; ierr = PetscOptionsReal("-eps","parameter","",user.param,&user.param,NULL);CHKERRQ(ierr); ierr = PetscOptionsEnd();CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ /* * ierr = PetscOptionsGetBool(NULL,"-monitor",&monitor,NULL);CHKERRQ(ierr); */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create necessary matrix and vectors, solve same ODE on every process - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr); ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,user.mx,user.mx);CHKERRQ(ierr); ierr = MatSetFromOptions(A);CHKERRQ(ierr); ierr = MatSetUp(A);CHKERRQ(ierr); ierr = MatGetVecs(A,&x,NULL);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create time stepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetType(ts,TSEIMEX);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts,NULL,RHSFunction,&user);CHKERRQ(ierr); ierr = TSSetIFunction(ts,NULL,FormIFunction,&user);CHKERRQ(ierr); ierr = TSSetIJacobian(ts,A,A,FormIJacobian,&user);CHKERRQ(ierr); ftime = 142; maxsteps = 100000; 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); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,x);CHKERRQ(ierr); ierr = TSGetTime(ts,&ftime);CHKERRQ(ierr); ierr = TSGetTimeStepNumber(ts,&steps);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD,"eps %g, steps %D, ftime %g\n",(double)user.param,steps,(double)ftime);CHKERRQ(ierr); /* ierr = VecView(x,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);*/ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = MatDestroy(&A);CHKERRQ(ierr); ierr = VecDestroy(&x);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }
int main(int argc,char **argv) { TS ts; /* nonlinear solver */ Vec u,r; /* solution, residual vector */ Mat J; /* Jacobian matrix */ PetscInt steps,maxsteps = 1000; /* iterations for convergence */ PetscErrorCode ierr; DM da; PetscReal ftime,dt; AppCtx user; /* user-defined work context */ PetscInitialize(&argc,&argv,(char*)0,help); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMDACreate2d(PETSC_COMM_WORLD, DMDA_BOUNDARY_NONE, DMDA_BOUNDARY_NONE,DMDA_STENCIL_STAR,-8,-8,PETSC_DECIDE,PETSC_DECIDE, 1,1,NULL,NULL,&da);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&u);CHKERRQ(ierr); ierr = VecDuplicate(u,&r);CHKERRQ(ierr); /* Initialize user application context */ user.c = -30.0; /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); ierr = TSSetType(ts,TSBEULER);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts,r,RHSFunction,&user);CHKERRQ(ierr); /* Set Jacobian */ ierr = DMCreateMatrix(da,MATAIJ,&J);CHKERRQ(ierr); ierr = TSSetRHSJacobian(ts,J,J,RHSJacobian,NULL);CHKERRQ(ierr); ftime = 1.0; ierr = TSSetDuration(ts,maxsteps,ftime);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(da,u,&user);CHKERRQ(ierr); dt = .01; ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,u);CHKERRQ(ierr); ierr = TSGetSolveTime(ts,&ftime);CHKERRQ(ierr); ierr = TSGetTimeStepNumber(ts,&steps);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = VecDestroy(&u);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }
int main(int argc,char **argv) { TS ts; /* time integrator */ TSAdapt adapt; Vec X; /* solution vector */ Mat J; /* Jacobian matrix */ PetscInt steps,maxsteps,ncells,xs,xm,i; PetscErrorCode ierr; PetscReal ftime,dt; char chemfile[PETSC_MAX_PATH_LEN] = "chem.inp",thermofile[PETSC_MAX_PATH_LEN] = "therm.dat"; struct _User user; TSConvergedReason reason; PetscBool showsolutions = PETSC_FALSE; char **snames,*names; Vec lambda; /* used with TSAdjoint for sensitivities */ ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Chemistry solver options","");CHKERRQ(ierr); ierr = PetscOptionsString("-chem","CHEMKIN input file","",chemfile,chemfile,sizeof(chemfile),NULL);CHKERRQ(ierr); ierr = PetscOptionsString("-thermo","NASA thermo input file","",thermofile,thermofile,sizeof(thermofile),NULL);CHKERRQ(ierr); user.pressure = 1.01325e5; /* Pascal */ ierr = PetscOptionsReal("-pressure","Pressure of reaction [Pa]","",user.pressure,&user.pressure,NULL);CHKERRQ(ierr); user.Tini = 1550; ierr = PetscOptionsReal("-Tini","Initial temperature [K]","",user.Tini,&user.Tini,NULL);CHKERRQ(ierr); user.diffus = 100; ierr = PetscOptionsReal("-diffus","Diffusion constant","",user.diffus,&user.diffus,NULL);CHKERRQ(ierr); ierr = PetscOptionsBool("-draw_solution","Plot the solution for each cell","",showsolutions,&showsolutions,NULL);CHKERRQ(ierr); user.diffusion = PETSC_TRUE; ierr = PetscOptionsBool("-diffusion","Have diffusion","",user.diffusion,&user.diffusion,NULL);CHKERRQ(ierr); user.reactions = PETSC_TRUE; ierr = PetscOptionsBool("-reactions","Have reactions","",user.reactions,&user.reactions,NULL);CHKERRQ(ierr); ierr = PetscOptionsEnd();CHKERRQ(ierr); ierr = TC_initChem(chemfile, thermofile, 0, 1.0);TCCHKERRQ(ierr); user.Nspec = TC_getNspec(); user.Nreac = TC_getNreac(); ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_PERIODIC,-1,user.Nspec+1,1,NULL,&user.dm);CHKERRQ(ierr); ierr = DMDAGetInfo(user.dm,NULL,&ncells,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL);CHKERRQ(ierr); user.dx = 1.0/ncells; /* Set the coordinates of the cell centers; note final ghost cell is at x coordinate 1.0 */ ierr = DMDASetUniformCoordinates(user.dm,0.0,1.0,0.0,1.0,0.0,1.0);CHKERRQ(ierr); /* set the names of each field in the DMDA based on the species name */ ierr = PetscMalloc1((user.Nspec+1)*LENGTHOFSPECNAME,&names);CHKERRQ(ierr); ierr = PetscStrcpy(names,"Temp");CHKERRQ(ierr); TC_getSnames(user.Nspec,names+LENGTHOFSPECNAME);CHKERRQ(ierr); ierr = PetscMalloc1((user.Nspec+2),&snames);CHKERRQ(ierr); for (i=0; i<user.Nspec+1; i++) snames[i] = names+i*LENGTHOFSPECNAME; snames[user.Nspec+1] = NULL; ierr = DMDASetFieldNames(user.dm,(const char * const *)snames);CHKERRQ(ierr); ierr = PetscFree(snames);CHKERRQ(ierr); ierr = PetscFree(names);CHKERRQ(ierr); ierr = DMCreateMatrix(user.dm,&J);CHKERRQ(ierr); ierr = DMCreateGlobalVector(user.dm,&X);CHKERRQ(ierr); ierr = PetscMalloc3(user.Nspec+1,&user.tchemwork,PetscSqr(user.Nspec+1),&user.Jdense,user.Nspec+1,&user.rows);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetDM(ts,user.dm);CHKERRQ(ierr); ierr = TSSetType(ts,TSARKIMEX);CHKERRQ(ierr); ierr = TSARKIMEXSetFullyImplicit(ts,PETSC_TRUE);CHKERRQ(ierr); ierr = TSARKIMEXSetType(ts,TSARKIMEX4);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts,NULL,FormRHSFunction,&user);CHKERRQ(ierr); ierr = TSSetRHSJacobian(ts,J,J,FormRHSJacobian,&user);CHKERRQ(ierr); ftime = 1.0; maxsteps = 10000; ierr = TSSetDuration(ts,maxsteps,ftime);CHKERRQ(ierr); ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_STEPOVER);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(ts,X,&user);CHKERRQ(ierr); ierr = TSSetSolution(ts,X);CHKERRQ(ierr); dt = 1e-10; /* Initial time step */ ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr); ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr); ierr = TSAdaptSetStepLimits(adapt,1e-12,1e-4);CHKERRQ(ierr); /* Also available with -ts_adapt_dt_min/-ts_adapt_dt_max */ ierr = TSSetMaxSNESFailures(ts,-1);CHKERRQ(ierr); /* Retry step an unlimited number of times */ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Pass information to graphical monitoring routine - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ if (showsolutions) { ierr = DMDAGetCorners(user.dm,&xs,NULL,NULL,&xm,NULL,NULL);CHKERRQ(ierr); for (i=xs;i<xs+xm;i++) { ierr = MonitorCell(ts,&user,i);CHKERRQ(ierr); } } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set final conditions for sensitivities - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(user.dm,&lambda);CHKERRQ(ierr); ierr = TSSetCostGradients(ts,1,&lambda,NULL);CHKERRQ(ierr); ierr = VecSetValue(lambda,0,1.0,INSERT_VALUES);CHKERRQ(ierr); ierr = VecAssemblyBegin(lambda);CHKERRQ(ierr); ierr = VecAssemblyEnd(lambda);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve ODE - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ 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 = PetscPrintf(PETSC_COMM_WORLD,"%s at time %g after %D steps\n",TSConvergedReasons[reason],(double)ftime,steps);CHKERRQ(ierr); { Vec max; const char * const *names; PetscInt i; const PetscReal *bmax; ierr = TSMonitorEnvelopeGetBounds(ts,&max,NULL);CHKERRQ(ierr); if (max) { ierr = TSMonitorLGGetVariableNames(ts,&names);CHKERRQ(ierr); if (names) { ierr = VecGetArrayRead(max,&bmax);CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_SELF,"Species - maximum mass fraction\n");CHKERRQ(ierr); for (i=1; i<user.Nspec; i++) { if (bmax[i] > .01) {ierr = PetscPrintf(PETSC_COMM_SELF,"%s %g\n",names[i],bmax[i]);CHKERRQ(ierr);} } ierr = VecRestoreArrayRead(max,&bmax);CHKERRQ(ierr); } } } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ TC_reset(); ierr = DMDestroy(&user.dm);CHKERRQ(ierr); ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = VecDestroy(&X);CHKERRQ(ierr); ierr = VecDestroy(&lambda);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = PetscFree3(user.tchemwork,user.Jdense,user.rows);CHKERRQ(ierr); ierr = PetscFinalize(); return ierr; }
int main(int argc,char **argv) { TS ts; /* time integrator */ SNES snes; /* nonlinear solver */ SNESLineSearch linesearch; /* line search */ Vec X; /* solution, residual vectors */ Mat J; /* Jacobian matrix */ PetscInt steps,maxsteps,mx; PetscErrorCode ierr; DM da; PetscReal ftime,dt; 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,DMDA_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[0] = 1; ierr = PetscOptionsReal("-a0","Advection rate 0","",user.a[0],&user.a[0],NULL);CHKERRQ(ierr); user.a[1] = 0; ierr = PetscOptionsReal("-a1","Advection rate 1","",user.a[1],&user.a[1],NULL);CHKERRQ(ierr); user.k[0] = 1e6; ierr = PetscOptionsReal("-k0","Reaction rate 0","",user.k[0],&user.k[0],NULL);CHKERRQ(ierr); user.k[1] = 2*user.k[0]; ierr = PetscOptionsReal("-k1","Reaction rate 1","",user.k[1],&user.k[1],NULL);CHKERRQ(ierr); user.s[0] = 0; ierr = PetscOptionsReal("-s0","Source 0","",user.s[0],&user.s[0],NULL);CHKERRQ(ierr); user.s[1] = 1; ierr = PetscOptionsReal("-s1","Source 1","",user.s[1],&user.s[1],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 = DMCreateMatrix(da,MATAIJ,&J);CHKERRQ(ierr); ierr = TSSetIJacobian(ts,J,J,FormIJacobian,&user);CHKERRQ(ierr); /* A line search in the nonlinear solve can fail due to ill-conditioning unless an absolute tolerance is set. Since * this problem is linear, we deactivate the line search. For a linear problem, it is usually recommended to also use * SNESSetType(snes,SNESKSPONLY). */ ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr); ierr = SNESGetLineSearch(snes,&linesearch);CHKERRQ(ierr); ierr = SNESLineSearchSetType(linesearch,SNESLINESEARCHBASIC);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); dt = .1 * PetscMax(user.a[0],user.a[1]) / mx; /* Advective CFL, I don't know why it needs so much safety factor. */ ierr = TSSetInitialTimeStep(ts,0.0,dt);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 = PetscPrintf(PETSC_COMM_WORLD,"%s at time %G after %D steps\n",TSConvergedReasons[reason],ftime,steps);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; }
int main(int argc,char **argv) { PetscErrorCode ierr; int time; /* amount of loops */ struct in put; PetscScalar rh; /* relative humidity */ PetscScalar x; /* memory varialbe for relative humidity calculation */ PetscScalar deep_grnd_temp; /* temperature of ground under top soil surface layer */ PetscScalar emma; /* absorption-emission constant for air */ PetscScalar pressure1 = 101300; /* surface pressure */ PetscScalar mixratio; /* mixing ratio */ PetscScalar airtemp; /* temperature of air near boundary layer inversion */ PetscScalar dewtemp; /* dew point temperature */ PetscScalar sfctemp; /* temperature at surface */ PetscScalar pwat; /* total column precipitable water */ PetscScalar cloudTemp; /* temperature at base of cloud */ AppCtx user; /* user-defined work context */ MonitorCtx usermonitor; /* user-defined monitor context */ PetscMPIInt rank,size; TS ts; SNES snes; DM da; Vec T,rhs; /* solution vector */ Mat J; /* Jacobian matrix */ PetscReal ftime,dt; PetscInt steps,dof = 5; PetscBool use_coloring = PETSC_TRUE; MatFDColoring matfdcoloring = 0; PetscBool monitor_off = PETSC_FALSE; PetscInitialize(&argc,&argv,(char*)0,help); ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr); ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr); /* Inputs */ readinput(&put); sfctemp = put.Ts; dewtemp = put.Td; cloudTemp = put.Tc; airtemp = put.Ta; pwat = put.pwt; if (!rank) PetscPrintf(PETSC_COMM_SELF,"Initial Temperature = %g\n",sfctemp); /* input surface temperature */ deep_grnd_temp = sfctemp - 10; /* set underlying ground layer temperature */ emma = emission(pwat); /* accounts for radiative effects of water vapor */ /* Converts from Fahrenheit to Celsuis */ sfctemp = fahr_to_cel(sfctemp); airtemp = fahr_to_cel(airtemp); dewtemp = fahr_to_cel(dewtemp); cloudTemp = fahr_to_cel(cloudTemp); deep_grnd_temp = fahr_to_cel(deep_grnd_temp); /* Converts from Celsius to Kelvin */ sfctemp += 273; airtemp += 273; dewtemp += 273; cloudTemp += 273; deep_grnd_temp += 273; /* Calculates initial relative humidity */ x = calcmixingr(dewtemp,pressure1); mixratio = calcmixingr(sfctemp,pressure1); rh = (x/mixratio)*100; if (!rank) printf("Initial RH = %.1f percent\n\n",rh); /* prints initial relative humidity */ time = 3600*put.time; /* sets amount of timesteps to run model */ /* Configure PETSc TS solver */ /*------------------------------------------*/ /* Create grid */ ierr = DMDACreate2d(PETSC_COMM_WORLD,DMDA_BOUNDARY_PERIODIC,DMDA_BOUNDARY_PERIODIC,DMDA_STENCIL_STAR,-20,-20, PETSC_DECIDE,PETSC_DECIDE,dof,1,NULL,NULL,&da);CHKERRQ(ierr); ierr = DMDASetUniformCoordinates(da, 0.0, 1.0, 0.0, 1.0, 0.0, 1.0);CHKERRQ(ierr); /* Define output window for each variable of interest */ ierr = DMDASetFieldName(da,0,"Ts");CHKERRQ(ierr); ierr = DMDASetFieldName(da,1,"Ta");CHKERRQ(ierr); ierr = DMDASetFieldName(da,2,"u");CHKERRQ(ierr); ierr = DMDASetFieldName(da,3,"v");CHKERRQ(ierr); ierr = DMDASetFieldName(da,4,"p");CHKERRQ(ierr); /* set values for appctx */ user.da = da; user.Ts = sfctemp; user.fract = put.fr; /* fraction of sky covered by clouds */ user.dewtemp = dewtemp; /* dew point temperature (mositure in air) */ user.csoil = 2000000; /* heat constant for layer */ user.dzlay = 0.08; /* thickness of top soil layer */ user.emma = emma; /* emission parameter */ user.wind = put.wnd; /* wind spped */ user.pressure1 = pressure1; /* sea level pressure */ user.airtemp = airtemp; /* temperature of air near boundar layer inversion */ user.Tc = cloudTemp; /* temperature at base of lowest cloud layer */ user.init = put.init; /* user chosen initiation scenario */ user.lat = 70*0.0174532; /* converts latitude degrees to latitude in radians */ user.deep_grnd_temp = deep_grnd_temp; /* temp in lowest ground layer */ /* set values for MonitorCtx */ usermonitor.drawcontours = PETSC_FALSE; ierr = PetscOptionsHasName(NULL,"-drawcontours",&usermonitor.drawcontours);CHKERRQ(ierr); if (usermonitor.drawcontours) { PetscReal bounds[] = {1000.0,-1000., -1000.,-1000., 1000.,-1000., 1000.,-1000., 1000,-1000, 100700,100800}; ierr = PetscViewerDrawOpen(PETSC_COMM_WORLD,0,0,0,0,300,300,&usermonitor.drawviewer);CHKERRQ(ierr); ierr = PetscViewerDrawSetBounds(usermonitor.drawviewer,dof,bounds);CHKERRQ(ierr); } usermonitor.interval = 1; ierr = PetscOptionsGetInt(NULL,"-monitor_interval",&usermonitor.interval,NULL);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DA; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&T);CHKERRQ(ierr); ierr = VecDuplicate(T,&rhs);CHKERRQ(ierr); /* r: vector to put the computed right hand side */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetType(ts,TSBEULER);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts,rhs,RhsFunc,&user);CHKERRQ(ierr); /* Set Jacobian evaluation routine - use coloring to compute finite difference Jacobian efficiently */ ierr = DMSetMatType(da,MATAIJ);CHKERRQ(ierr); ierr = DMCreateMatrix(da,&J);CHKERRQ(ierr); ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr); if (use_coloring) { ISColoring iscoloring; ierr = DMCreateColoring(da,IS_COLORING_GLOBAL,&iscoloring);CHKERRQ(ierr); ierr = MatFDColoringCreate(J,iscoloring,&matfdcoloring);CHKERRQ(ierr); ierr = MatFDColoringSetFromOptions(matfdcoloring);CHKERRQ(ierr); ierr = MatFDColoringSetUp(J,iscoloring,matfdcoloring);CHKERRQ(ierr); ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr); ierr = MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))SNESTSFormFunction,ts);CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefaultColor,matfdcoloring);CHKERRQ(ierr); } else { ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefault,NULL);CHKERRQ(ierr); } /* Define what to print for ts_monitor option */ ierr = PetscOptionsHasName(NULL,"-monitor_off",&monitor_off);CHKERRQ(ierr); if (!monitor_off) { ierr = TSMonitorSet(ts,Monitor,&usermonitor,NULL);CHKERRQ(ierr); } ierr = FormInitialSolution(da,T,&user);CHKERRQ(ierr); dt = TIMESTEP; /* initial time step */ ftime = TIMESTEP*time; if (!rank) printf("time %d, ftime %g hour, TIMESTEP %g\n",time,ftime/3600,dt); ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr); ierr = TSSetDuration(ts,time,ftime);CHKERRQ(ierr); ierr = TSSetSolution(ts,T);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,T);CHKERRQ(ierr); ierr = TSGetSolveTime(ts,&ftime);CHKERRQ(ierr); ierr = TSGetTimeStepNumber(ts,&steps);CHKERRQ(ierr); if (!rank) PetscPrintf(PETSC_COMM_WORLD,"Solution T after %g hours %d steps\n",ftime/3600,steps); if (matfdcoloring) {ierr = MatFDColoringDestroy(&matfdcoloring);CHKERRQ(ierr);} if (usermonitor.drawcontours) { ierr = PetscViewerDestroy(&usermonitor.drawviewer);CHKERRQ(ierr); } ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = VecDestroy(&T);CHKERRQ(ierr); ierr = VecDestroy(&rhs);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); PetscFinalize(); return 0; }
int main(int argc,char **argv) { TS ts; /* nonlinear solver */ Vec u,r; /* solution, residual vectors */ Mat J,Jmf = PETSC_NULL; /* Jacobian matrices */ PetscInt maxsteps = 1000; /* iterations for convergence */ PetscErrorCode ierr; DM da; PetscReal dt; AppCtx user; /* user-defined work context */ SNES snes; PetscInt Jtype; /* Jacobian type 0: user provide Jacobian; 1: slow finite difference; 2: fd with coloring; */ PetscInitialize(&argc,&argv,(char *)0,help); /* Initialize user application context */ user.da = PETSC_NULL; user.nstencilpts = 5; user.c = -30.0; user.boundary = 0; /* 0: Drichlet BC; 1: Neumann BC */ user.viewJacobian = PETSC_FALSE; ierr = PetscOptionsGetInt(PETSC_NULL,"-nstencilpts",&user.nstencilpts,PETSC_NULL);CHKERRQ(ierr); ierr = PetscOptionsGetInt(PETSC_NULL,"-boundary",&user.boundary,PETSC_NULL);CHKERRQ(ierr); ierr = PetscOptionsHasName(PETSC_NULL,"-viewJacobian",&user.viewJacobian);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ if (user.nstencilpts == 5){ ierr = DMDACreate2d(PETSC_COMM_WORLD, DMDA_BOUNDARY_NONE, DMDA_BOUNDARY_NONE,DMDA_STENCIL_STAR,-11,-11,PETSC_DECIDE,PETSC_DECIDE,1,1,PETSC_NULL,PETSC_NULL,&da);CHKERRQ(ierr); } else if (user.nstencilpts == 9){ ierr = DMDACreate2d(PETSC_COMM_WORLD, DMDA_BOUNDARY_NONE, DMDA_BOUNDARY_NONE,DMDA_STENCIL_BOX,-11,-11,PETSC_DECIDE,PETSC_DECIDE,1,1,PETSC_NULL,PETSC_NULL,&da);CHKERRQ(ierr); } else { SETERRQ1(PETSC_COMM_WORLD,PETSC_ERR_SUP,"nstencilpts %d is not supported",user.nstencilpts); } user.da = da; /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&u);CHKERRQ(ierr); ierr = VecDuplicate(u,&r);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetType(ts,TSBEULER);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); ierr = TSSetIFunction(ts,r,FormIFunction,&user);CHKERRQ(ierr); ierr = TSSetDuration(ts,maxsteps,1.0);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(u,&user);CHKERRQ(ierr); ierr = TSSetSolution(ts,u);CHKERRQ(ierr); dt = .01; ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set Jacobian evaluation routine - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateMatrix(da,MATAIJ,&J);CHKERRQ(ierr); Jtype = 0; ierr = PetscOptionsGetInt(PETSC_NULL, "-Jtype",&Jtype,PETSC_NULL);CHKERRQ(ierr); if (Jtype == 0){ /* use user provided Jacobian evaluation routine */ if (user.nstencilpts != 5) SETERRQ1(PETSC_COMM_WORLD,PETSC_ERR_SUP,"user Jacobian routine FormIJacobian() does not support nstencilpts=%D",user.nstencilpts); ierr = TSSetIJacobian(ts,J,J,FormIJacobian,&user);CHKERRQ(ierr); } else { /* use finite difference Jacobian J as preconditioner and '-snes_mf_operator' for Mat*vec */ ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr); ierr = MatCreateSNESMF(snes,&Jmf);CHKERRQ(ierr); if (Jtype == 1){ /* slow finite difference J; */ ierr = SNESSetJacobian(snes,Jmf,J,SNESDefaultComputeJacobian,PETSC_NULL);CHKERRQ(ierr); } else if (Jtype == 2){ /* Use coloring to compute finite difference J efficiently */ ierr = SNESSetJacobian(snes,Jmf,J,SNESDefaultComputeJacobianColor,0);CHKERRQ(ierr); } else SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Jtype is not supported"); } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Sets various TS parameters from user options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,u);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = MatDestroy(&Jmf);CHKERRQ(ierr); ierr = VecDestroy(&u);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }
int main(int argc,char **argv) { TS ts; /* nonlinear solver */ Vec x,r; /* solution, residual vectors */ PetscInt steps,maxsteps = 100; /* iterations for convergence */ PetscErrorCode ierr; DM da; PetscReal ftime; SNES ts_snes; /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Initialize program - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ PetscInitialize(&argc,&argv,(char*)0,help); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMDACreate2d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, DM_BOUNDARY_NONE,DMDA_STENCIL_STAR,-8,-8,PETSC_DECIDE,PETSC_DECIDE, 2,1,NULL,NULL,&da);CHKERRQ(ierr); ierr = DMDASetFieldName(da,0,"u");CHKERRQ(ierr); ierr = DMDASetFieldName(da,1,"v");CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; then duplicate for remaining vectors that are the same types - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&x);CHKERRQ(ierr); ierr = VecDuplicate(x,&r);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts,NULL,FormFunction,da);CHKERRQ(ierr); ierr = TSSetDuration(ts,maxsteps,1.0);CHKERRQ(ierr); ierr = TSMonitorSet(ts,MyTSMonitor,0,0);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Customize nonlinear solver - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetType(ts,TSBEULER);CHKERRQ(ierr); ierr = TSGetSNES(ts,&ts_snes); ierr = SNESMonitorSet(ts_snes,MySNESMonitor,NULL,NULL); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(da,x);CHKERRQ(ierr); ierr = TSSetInitialTimeStep(ts,0.0,.0001);CHKERRQ(ierr); ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_STEPOVER);CHKERRQ(ierr); ierr = TSSetSolution(ts,x);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); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. All PETSc objects should be destroyed when they are no longer needed. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = VecDestroy(&x);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }
int main(int argc,char **argv) { 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; 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,DMDA_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 = 0.02; 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 = DMCreateMatrix(da,MATAIJ,&J);CHKERRQ(ierr); ierr = TSSetIJacobian(ts,J,J,FormIJacobian,&user);CHKERRQ(ierr); ftime = 10.0; 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 */ ierr = TSSetInitialTimeStep(ts,0.0,dt);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 = PetscPrintf(PETSC_COMM_WORLD,"%s at time %G after %D steps\n",TSConvergedReasons[reason],ftime,steps);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; }
int main(int argc,char **argv) { TS ts; /* time integrator */ Vec x,r; /* solution, residual vectors */ PetscInt steps,Mx; PetscErrorCode ierr; DM da; PetscReal dt; UserCtx ctx; PetscBool mymonitor; PetscViewer viewer; PetscBool flg; /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Initialize program - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; ctx.kappa = 1.0; ierr = PetscOptionsGetReal(NULL,NULL,"-kappa",&ctx.kappa,NULL);CHKERRQ(ierr); ctx.allencahn = PETSC_FALSE; ierr = PetscOptionsHasName(NULL,NULL,"-allen-cahn",&ctx.allencahn);CHKERRQ(ierr); ierr = PetscOptionsHasName(NULL,NULL,"-mymonitor",&mymonitor);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMDACreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_PERIODIC, 10,1,2,NULL,&da);CHKERRQ(ierr); ierr = DMSetFromOptions(da);CHKERRQ(ierr); ierr = DMSetUp(da);CHKERRQ(ierr); ierr = DMDASetFieldName(da,0,"Heat equation: u");CHKERRQ(ierr); ierr = DMDAGetInfo(da,0,&Mx,0,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr); dt = 1.0/(ctx.kappa*Mx*Mx); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; then duplicate for remaining vectors that are the same types - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&x);CHKERRQ(ierr); ierr = VecDuplicate(x,&r);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts,NULL,FormFunction,&ctx);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Customize nonlinear solver - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetType(ts,TSCN);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(da,x);CHKERRQ(ierr); ierr = TSSetTimeStep(ts,dt);CHKERRQ(ierr); ierr = TSSetMaxTime(ts,.02);CHKERRQ(ierr); ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_INTERPOLATE);CHKERRQ(ierr); ierr = TSSetSolution(ts,x);CHKERRQ(ierr); if (mymonitor) { ctx.ports = NULL; ierr = TSMonitorSet(ts,MyMonitor,&ctx,MyDestroy);CHKERRQ(ierr); } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,x);CHKERRQ(ierr); ierr = TSGetStepNumber(ts,&steps);CHKERRQ(ierr); ierr = PetscOptionsHasName(NULL,NULL,"-square_initial",&flg);CHKERRQ(ierr); if (flg) { ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,"InitialSolution.heat",FILE_MODE_WRITE,&viewer);CHKERRQ(ierr); ierr = VecView(x,viewer);CHKERRQ(ierr); ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr); } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. All PETSc objects should be destroyed when they are no longer needed. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = VecDestroy(&x);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); return ierr; }
int main(int argc, char **argv) { DM dm; TS ts; Vec X; Mat J; PetscInt steps, maxsteps, mx; PetscReal ftime, hx, dt; TSConvergedReason reason; struct _User user; PetscErrorCode ierr; ierr = PetscInitialize(&argc, &argv, NULL,help);if (ierr) return ierr; ierr = DMDACreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_NONE, -11, 3, 1, NULL, &dm);CHKERRQ(ierr); ierr = DMSetFromOptions(dm);CHKERRQ(ierr); ierr = DMSetUp(dm);CHKERRQ(ierr); ierr = DMDASetUniformCoordinates(dm, 0.0, 20.0, 0.0, 0.0, 0.0, 0.0);CHKERRQ(ierr); ierr = DMCreateGlobalVector(dm, &X);CHKERRQ(ierr); ierr = PetscOptionsBegin(PETSC_COMM_WORLD, NULL, "Dynamic Friction Options", ""); { user.epsilon = 0.1; user.gamma = 0.5; user.gammaTilde = 0.5; user.xi = 0.5; user.c = 0.5; ierr = PetscOptionsReal("-epsilon", "Inverse of seismic ratio", "", user.epsilon, &user.epsilon, NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-gamma", "Wave frequency for interblock coupling", "", user.gamma, &user.gamma, NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-gamma_tilde", "Wave frequency for plate coupling", "", user.gammaTilde, &user.gammaTilde, NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-xi", "Interblock spring constant", "", user.xi, &user.xi, NULL);CHKERRQ(ierr); ierr = PetscOptionsReal("-c", "Wavespeed", "", user.c, &user.c, NULL);CHKERRQ(ierr); } ierr = PetscOptionsEnd();CHKERRQ(ierr); ierr = TSCreate(PETSC_COMM_WORLD, &ts);CHKERRQ(ierr); ierr = TSSetDM(ts, dm);CHKERRQ(ierr); ierr = TSSetRHSFunction(ts, NULL, FormRHSFunction, &user);CHKERRQ(ierr); ierr = TSSetIFunction(ts, NULL, FormIFunction, &user);CHKERRQ(ierr); ierr = DMSetMatType(dm, MATAIJ);CHKERRQ(ierr); ierr = DMCreateMatrix(dm, &J);CHKERRQ(ierr); ierr = TSSetIJacobian(ts, J, J, FormIJacobian, &user);CHKERRQ(ierr); ftime = 800.0; maxsteps = 10000; ierr = TSSetDuration(ts, maxsteps, ftime);CHKERRQ(ierr); ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_STEPOVER);CHKERRQ(ierr); ierr = FormInitialSolution(ts, X, &user);CHKERRQ(ierr); ierr = TSSetSolution(ts, X);CHKERRQ(ierr); ierr = VecGetSize(X, &mx);CHKERRQ(ierr); hx = 20.0/(PetscReal)(mx-1); dt = 0.4 * PetscSqr(hx) / PetscSqr(user.c); /* Diffusive stability limit */ ierr = TSSetInitialTimeStep(ts, 0.0, dt);CHKERRQ(ierr); ierr = TSSetFromOptions(ts);CHKERRQ(ierr); 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 = PetscPrintf(PETSC_COMM_WORLD, "%s at time %g after %D steps\n", TSConvergedReasons[reason], (double)ftime, steps);CHKERRQ(ierr); ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = VecDestroy(&X);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&dm);CHKERRQ(ierr); ierr = PetscFinalize(); return ierr; }
int main(int argc,char **argv) { TS ts; /* nonlinear solver */ Vec x,r; /* solution, residual vectors */ Mat J; /* Jacobian matrix */ PetscInt steps,Mx,maxsteps = 10000000; PetscErrorCode ierr; DM da; MatFDColoring matfdcoloring; ISColoring iscoloring; PetscReal dt; PetscReal vbounds[] = {-100000,100000,-1.1,1.1}; PetscBool wait; Vec ul,uh; SNES snes; UserCtx ctx; /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Initialize program - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr; ctx.kappa = 1.0; ierr = PetscOptionsGetReal(NULL,"-kappa",&ctx.kappa,NULL);CHKERRQ(ierr); ctx.cahnhillard = PETSC_FALSE; ierr = PetscOptionsGetBool(NULL,NULL,"-cahn-hillard",&ctx.cahnhillard,NULL);CHKERRQ(ierr); ierr = PetscViewerDrawSetBounds(PETSC_VIEWER_DRAW_(PETSC_COMM_WORLD),2,vbounds);CHKERRQ(ierr); ierr = PetscViewerDrawResize(PETSC_VIEWER_DRAW_(PETSC_COMM_WORLD),600,600);CHKERRQ(ierr); ctx.energy = 1; /* ierr = PetscOptionsGetInt(NULL,NULL,"-energy",&ctx.energy,NULL);CHKERRQ(ierr); */ ierr = PetscOptionsGetInt(NULL,NULL,"-energy",&ctx.energy,NULL);CHKERRQ(ierr); ctx.tol = 1.0e-8; ierr = PetscOptionsGetReal(NULL,"-tol",&ctx.tol,NULL);CHKERRQ(ierr); ctx.theta = .001; ctx.theta_c = 1.0; ierr = PetscOptionsGetReal(NULL,"-theta",&ctx.theta,NULL);CHKERRQ(ierr); ierr = PetscOptionsGetReal(NULL,"-theta_c",&ctx.theta_c,NULL);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMDACreate1d(PETSC_COMM_WORLD, DM_BOUNDARY_PERIODIC, -10,2,2,NULL,&da);CHKERRQ(ierr); ierr = DMSetFromOptions(da);CHKERRQ(ierr); ierr = DMSetUp(da);CHKERRQ(ierr); ierr = DMDASetFieldName(da,0,"Biharmonic heat equation: w = -kappa*u_xx");CHKERRQ(ierr); ierr = DMDASetFieldName(da,1,"Biharmonic heat equation: u");CHKERRQ(ierr); ierr = DMDAGetInfo(da,0,&Mx,0,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr); dt = 1.0/(10.*ctx.kappa*Mx*Mx*Mx*Mx); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; then duplicate for remaining vectors that are the same types - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&x);CHKERRQ(ierr); ierr = VecDuplicate(x,&r);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetIFunction(ts,NULL,FormFunction,&ctx);CHKERRQ(ierr); ierr = TSSetDuration(ts,maxsteps,.02);CHKERRQ(ierr); ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_STEPOVER);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create matrix data structure; set Jacobian evaluation routine < Set Jacobian matrix data structure and default Jacobian evaluation routine. User can override with: -snes_mf : matrix-free Newton-Krylov method with no preconditioning (unless user explicitly sets preconditioner) -snes_mf_operator : form preconditioning matrix as set by the user, but use matrix-free approx for Jacobian-vector products within Newton-Krylov method - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr); ierr = DMCreateColoring(da,IS_COLORING_GLOBAL,&iscoloring);CHKERRQ(ierr); ierr = DMSetMatType(da,MATAIJ);CHKERRQ(ierr); ierr = DMCreateMatrix(da,&J);CHKERRQ(ierr); ierr = MatFDColoringCreate(J,iscoloring,&matfdcoloring);CHKERRQ(ierr); ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr); ierr = MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode (*)(void))SNESTSFormFunction,ts);CHKERRQ(ierr); ierr = MatFDColoringSetFromOptions(matfdcoloring);CHKERRQ(ierr); ierr = MatFDColoringSetUp(J,iscoloring,matfdcoloring);CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefaultColor,matfdcoloring);CHKERRQ(ierr); { ierr = VecDuplicate(x,&ul);CHKERRQ(ierr); ierr = VecDuplicate(x,&uh);CHKERRQ(ierr); ierr = VecStrideSet(ul,0,PETSC_NINFINITY);CHKERRQ(ierr); ierr = VecStrideSet(ul,1,-1.0);CHKERRQ(ierr); ierr = VecStrideSet(uh,0,PETSC_INFINITY);CHKERRQ(ierr); ierr = VecStrideSet(uh,1,1.0);CHKERRQ(ierr); ierr = TSVISetVariableBounds(ts,ul,uh);CHKERRQ(ierr); } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Customize nonlinear solver - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetType(ts,TSBEULER);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(da,x,ctx.kappa);CHKERRQ(ierr); ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr); ierr = TSSetSolution(ts,x);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,x);CHKERRQ(ierr); wait = PETSC_FALSE; ierr = PetscOptionsGetBool(NULL,NULL,"-wait",&wait,NULL);CHKERRQ(ierr); if (wait) { ierr = PetscSleep(-1);CHKERRQ(ierr); } ierr = TSGetTimeStepNumber(ts,&steps);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. All PETSc objects should be destroyed when they are no longer needed. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ { ierr = VecDestroy(&ul);CHKERRQ(ierr); ierr = VecDestroy(&uh);CHKERRQ(ierr); } ierr = MatDestroy(&J);CHKERRQ(ierr); ierr = MatFDColoringDestroy(&matfdcoloring);CHKERRQ(ierr); ierr = VecDestroy(&x);CHKERRQ(ierr); ierr = VecDestroy(&r);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }
int main(int argc,char **argv) { TS ts; /* nonlinear solver */ Vec u; /* solution, residual vectors */ Mat J; /* Jacobian matrix */ PetscInt steps,maxsteps = 1000; /* iterations for convergence */ PetscErrorCode ierr; DM da; MatFDColoring matfdcoloring = PETSC_NULL; PetscReal ftime,dt; MonitorCtx usermonitor; /* user-defined monitor context */ AppCtx user; /* user-defined work context */ JacobianType jacType; PetscInitialize(&argc,&argv,(char *)0,help); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMDACreate1d(PETSC_COMM_WORLD,DMDA_BOUNDARY_NONE,-11,1,1,PETSC_NULL,&da);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&u);CHKERRQ(ierr); /* Initialize user application context */ user.c = -30.0; user.boundary = 0; /* 0: Dirichlet BC; 1: Neumann BC */ user.viewJacobian = PETSC_FALSE; ierr = PetscOptionsGetInt(PETSC_NULL,"-boundary",&user.boundary,PETSC_NULL);CHKERRQ(ierr); ierr = PetscOptionsHasName(PETSC_NULL,"-viewJacobian",&user.viewJacobian);CHKERRQ(ierr); usermonitor.drawcontours = PETSC_FALSE; ierr = PetscOptionsHasName(PETSC_NULL,"-drawcontours",&usermonitor.drawcontours);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts);CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR);CHKERRQ(ierr); ierr = TSSetType(ts,TSTHETA);CHKERRQ(ierr); ierr = TSThetaSetTheta(ts,1.0);CHKERRQ(ierr); /* Make the Theta method behave like backward Euler */ ierr = TSSetIFunction(ts,PETSC_NULL,FormIFunction,&user);CHKERRQ(ierr); ierr = DMCreateMatrix(da,MATAIJ,&J);CHKERRQ(ierr); jacType = JACOBIAN_ANALYTIC; /* use user-provide Jacobian */ ierr = TSSetIJacobian(ts,J,J,FormIJacobian,&user);CHKERRQ(ierr); ierr = TSSetDM(ts,da);CHKERRQ(ierr); /* Use TSGetDM() to access. Setting here allows easy use of geometric multigrid. */ ftime = 1.0; ierr = TSSetDuration(ts,maxsteps,ftime);CHKERRQ(ierr); ierr = TSMonitorSet(ts,MyTSMonitor,&usermonitor,PETSC_NULL);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(ts,u,&user);CHKERRQ(ierr); ierr = TSSetSolution(ts,u);CHKERRQ(ierr); dt = .01; ierr = TSSetInitialTimeStep(ts,0.0,dt);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts);CHKERRQ(ierr); /* Use slow fd Jacobian or fast fd Jacobian with colorings. Note: this requirs snes which is not created until TSSetUp()/TSSetFromOptions() is called */ ierr = PetscOptionsBegin(((PetscObject)da)->comm,PETSC_NULL,"Options for Jacobian evaluation",PETSC_NULL);CHKERRQ(ierr); ierr = PetscOptionsEnum("-jac_type","Type of Jacobian","",JacobianTypes,(PetscEnum)jacType,(PetscEnum*)&jacType,0);CHKERRQ(ierr); ierr = PetscOptionsEnd();CHKERRQ(ierr); if (jacType == JACOBIAN_FD_COLORING) { SNES snes; ISColoring iscoloring; ierr = DMCreateColoring(da,IS_COLORING_GLOBAL,MATAIJ,&iscoloring);CHKERRQ(ierr); ierr = MatFDColoringCreate(J,iscoloring,&matfdcoloring);CHKERRQ(ierr); ierr = MatFDColoringSetFromOptions(matfdcoloring);CHKERRQ(ierr); ierr = ISColoringDestroy(&iscoloring);CHKERRQ(ierr); ierr = MatFDColoringSetFunction(matfdcoloring,(PetscErrorCode(*)(void))SNESTSFormFunction,ts);CHKERRQ(ierr); ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,SNESDefaultComputeJacobianColor,matfdcoloring);CHKERRQ(ierr); } else if (jacType == JACOBIAN_FD_FULL){ SNES snes; ierr = TSGetSNES(ts,&snes);CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,SNESDefaultComputeJacobian,&user);CHKERRQ(ierr); } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Solve nonlinear system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,u,&ftime);CHKERRQ(ierr); ierr = TSGetTimeStepNumber(ts,&steps);CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = MatDestroy(&J);CHKERRQ(ierr); if (matfdcoloring) {ierr = MatFDColoringDestroy(&matfdcoloring);CHKERRQ(ierr);} ierr = VecDestroy(&u);CHKERRQ(ierr); ierr = TSDestroy(&ts);CHKERRQ(ierr); ierr = DMDestroy(&da);CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }
int main(int argc,char **argv) { TS ts; /* nonlinear solver */ Vec u; /* solution, residual vectors */ Mat J; /* Jacobian matrix */ PetscInt maxsteps = 1000; /* iterations for convergence */ PetscInt nsteps; PetscReal vmin,vmax,norm; PetscErrorCode ierr; DM da; PetscReal ftime,dt; AppCtx user; /* user-defined work context */ JacobianType jacType; PetscInitialize(&argc,&argv,(char*)0,help); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create distributed array (DMDA) to manage parallel grid and vectors - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMDACreate1d(PETSC_COMM_WORLD,DMDA_BOUNDARY_NONE,-11,1,1,NULL,&da); CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Extract global vectors from DMDA; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = DMCreateGlobalVector(da,&u); CHKERRQ(ierr); /* Initialize user application context */ user.c = -30.0; user.boundary = 0; /* 0: Dirichlet BC; 1: Neumann BC */ user.viewJacobian = PETSC_FALSE; ierr = PetscOptionsGetInt(NULL,"-boundary",&user.boundary,NULL); CHKERRQ(ierr); ierr = PetscOptionsHasName(NULL,"-viewJacobian",&user.viewJacobian); CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Create timestepping solver context - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSCreate(PETSC_COMM_WORLD,&ts); CHKERRQ(ierr); ierr = TSSetProblemType(ts,TS_NONLINEAR); CHKERRQ(ierr); ierr = TSSetType(ts,TSTHETA); CHKERRQ(ierr); ierr = TSThetaSetTheta(ts,1.0); CHKERRQ(ierr); /* Make the Theta method behave like backward Euler */ ierr = TSSetIFunction(ts,NULL,FormIFunction,&user); CHKERRQ(ierr); ierr = DMSetMatType(da,MATAIJ); CHKERRQ(ierr); ierr = DMCreateMatrix(da,&J); CHKERRQ(ierr); jacType = JACOBIAN_ANALYTIC; /* use user-provide Jacobian */ ierr = TSSetDM(ts,da); CHKERRQ(ierr); /* Use TSGetDM() to access. Setting here allows easy use of geometric multigrid. */ ftime = 1.0; ierr = TSSetDuration(ts,maxsteps,ftime); CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set initial conditions - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = FormInitialSolution(ts,u,&user); CHKERRQ(ierr); ierr = TSSetSolution(ts,u); CHKERRQ(ierr); dt = .01; ierr = TSSetInitialTimeStep(ts,0.0,dt); CHKERRQ(ierr); /* Use slow fd Jacobian or fast fd Jacobian with colorings. Note: this requirs snes which is not created until TSSetUp()/TSSetFromOptions() is called */ ierr = PetscOptionsBegin(PETSC_COMM_WORLD,NULL,"Options for Jacobian evaluation",NULL); CHKERRQ(ierr); ierr = PetscOptionsEnum("-jac_type","Type of Jacobian","",JacobianTypes,(PetscEnum)jacType,(PetscEnum*)&jacType,0); CHKERRQ(ierr); ierr = PetscOptionsEnd(); CHKERRQ(ierr); if (jacType == JACOBIAN_ANALYTIC) { ierr = TSSetIJacobian(ts,J,J,FormIJacobian,&user); CHKERRQ(ierr); } else if (jacType == JACOBIAN_FD_COLORING) { SNES snes; ierr = TSGetSNES(ts,&snes); CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefaultColor,0); CHKERRQ(ierr); } else if (jacType == JACOBIAN_FD_FULL) { SNES snes; ierr = TSGetSNES(ts,&snes); CHKERRQ(ierr); ierr = SNESSetJacobian(snes,J,J,SNESComputeJacobianDefault,&user); CHKERRQ(ierr); } /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Set runtime options - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSetFromOptions(ts); CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Integrate ODE system - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = TSSolve(ts,u); CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Compute diagnostics of the solution - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = VecNorm(u,NORM_1,&norm); CHKERRQ(ierr); ierr = VecMax(u,NULL,&vmax); CHKERRQ(ierr); ierr = VecMin(u,NULL,&vmin); CHKERRQ(ierr); ierr = TSGetTimeStepNumber(ts,&nsteps); CHKERRQ(ierr); ierr = TSGetTime(ts,&ftime); CHKERRQ(ierr); ierr = PetscPrintf(PETSC_COMM_WORLD,"timestep %D: time %G, solution norm %G, max %G, min %G\n",nsteps,ftime,norm,vmax,vmin); CHKERRQ(ierr); /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Free work space. - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ ierr = MatDestroy(&J); CHKERRQ(ierr); ierr = VecDestroy(&u); CHKERRQ(ierr); ierr = TSDestroy(&ts); CHKERRQ(ierr); ierr = DMDestroy(&da); CHKERRQ(ierr); ierr = PetscFinalize(); PetscFunctionReturn(0); }