1 #define PETSCTS_DLL 2 3 #include "private/tsimpl.h" /*I "petscts.h" I*/ 4 5 #if 0 6 #undef __FUNCT__ 7 #define __FUNCT__ "TSPublish_Petsc" 8 static PetscErrorCode TSPublish_Petsc(PetscObject obj) 9 { 10 PetscFunctionBegin; 11 PetscFunctionReturn(0); 12 } 13 #endif 14 15 #undef __FUNCT__ 16 #define __FUNCT__ "TSCreate" 17 /*@C 18 TSCreate - This function creates an empty timestepper. The problem type can then be set with TSSetProblemType() and the 19 type of solver can then be set with TSSetType(). 20 21 Collective on MPI_Comm 22 23 Input Parameter: 24 . comm - The communicator 25 26 Output Parameter: 27 . ts - The TS 28 29 Level: beginner 30 31 .keywords: TS, create 32 .seealso: TSSetType(), TSSetUp(), TSDestroy(), MeshCreate(), TSSetProblemType() 33 @*/ 34 PetscErrorCode PETSCTS_DLLEXPORT TSCreate(MPI_Comm comm, TS *ts) { 35 TS t; 36 PetscErrorCode ierr; 37 38 PetscFunctionBegin; 39 PetscValidPointer(ts,1); 40 *ts = PETSC_NULL; 41 #ifndef PETSC_USE_DYNAMIC_LIBRARIES 42 ierr = TSInitializePackage(PETSC_NULL);CHKERRQ(ierr); 43 #endif 44 45 ierr = PetscHeaderCreate(t, _p_TS, struct _TSOps, TS_COOKIE, -1, "TS", comm, TSDestroy, TSView);CHKERRQ(ierr); 46 ierr = PetscMemzero(t->ops, sizeof(struct _TSOps));CHKERRQ(ierr); 47 48 t->ops->prestep = TSDefaultPreStep; 49 t->ops->update = TSDefaultUpdate; 50 t->ops->poststep = TSDefaultPostStep; 51 52 /* General TS description */ 53 t->problem_type = TS_LINEAR; 54 t->vec_sol = PETSC_NULL; 55 t->vec_sol_always = PETSC_NULL; 56 t->numbermonitors = 0; 57 t->isExplicit = PETSC_NULL; 58 t->Iindex = PETSC_NULL; 59 t->ksp = PETSC_NULL; 60 t->A = PETSC_NULL; 61 t->B = PETSC_NULL; 62 t->Arhs = PETSC_NULL; 63 t->Alhs = PETSC_NULL; 64 t->matflg = DIFFERENT_NONZERO_PATTERN; 65 t->snes = PETSC_NULL; 66 t->funP = PETSC_NULL; 67 t->jacP = PETSC_NULL; 68 t->setupcalled = 0; 69 t->data = PETSC_NULL; 70 t->user = PETSC_NULL; 71 t->max_steps = 5000; 72 t->max_time = 5.0; 73 t->time_step = .1; 74 t->time_step_old = t->time_step; 75 t->initial_time_step = t->time_step; 76 t->steps = 0; 77 t->ptime = 0.0; 78 t->linear_its = 0; 79 t->nonlinear_its = 0; 80 t->work = PETSC_NULL; 81 t->nwork = 0; 82 83 *ts = t; 84 PetscFunctionReturn(0); 85 } 86 87 /* Set A = 1/dt*Alhs - A, B = 1/dt*Blhs - B */ 88 #undef __FUNCT__ 89 #define __FUNCT__ "TSScaleShiftMatrices" 90 PetscErrorCode TSScaleShiftMatrices(TS ts,Mat A,Mat B,MatStructure str) 91 { 92 PetscTruth flg; 93 PetscErrorCode ierr; 94 PetscScalar mdt = 1.0/ts->time_step; 95 96 PetscFunctionBegin; 97 /* this function requires additional work! */ 98 ierr = PetscTypeCompare((PetscObject)A,MATMFFD,&flg);CHKERRQ(ierr); 99 if (!flg) { 100 ierr = MatScale(A,-1.0);CHKERRQ(ierr); 101 if (ts->Alhs){ 102 ierr = MatAXPY(A,mdt,ts->Alhs,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr); 103 } else { 104 ierr = MatShift(A,mdt);CHKERRQ(ierr); 105 } 106 } 107 if (B != A && str != SAME_PRECONDITIONER) { 108 ierr = MatScale(B,-1.0);CHKERRQ(ierr); 109 ierr = MatShift(B,mdt);CHKERRQ(ierr); 110 } 111 PetscFunctionReturn(0); 112 } 113