Actual source code: ex14.c
1: static char help[] = "Tests all TSRK types \n\n";
3: #include <petscts.h>
5: static PetscErrorCode RHSFunction(TS ts, PetscReal t, Vec X, Vec F, void *ctx)
6: {
7: PetscInt i, n;
8: const PetscScalar *xx;
9: /* */ PetscScalar *ff;
11: PetscFunctionBeginUser;
12: PetscCall(VecGetLocalSize(X, &n));
13: PetscCall(VecGetArrayRead(X, &xx));
14: PetscCall(VecGetArray(F, &ff));
16: if (n >= 1) ff[0] = 1;
17: for (i = 1; i < n; i++) ff[i] = (i + 1) * (xx[i - 1] + PetscPowReal(t, i)) / 2;
19: PetscCall(VecRestoreArrayRead(X, &xx));
20: PetscCall(VecRestoreArray(F, &ff));
21: PetscFunctionReturn(PETSC_SUCCESS);
22: }
24: PetscErrorCode TestCheckStage(TSAdapt adapt, TS ts, PetscReal t, Vec X, PetscBool *accept)
25: {
26: PetscInt step;
28: PetscFunctionBeginUser;
29: PetscCall(TSGetStepNumber(ts, &step));
30: *accept = (step >= 2) ? PETSC_FALSE : PETSC_TRUE;
31: PetscFunctionReturn(PETSC_SUCCESS);
32: }
34: static PetscErrorCode TestExplicitTS(TS ts, PetscInt order, const char subtype[])
35: {
36: PetscInt i;
37: PetscReal t;
38: Vec U, X, Y;
39: TSType type;
40: PetscBool done;
41: const PetscScalar *xx;
42: const PetscScalar *yy;
43: const PetscReal Tf = 1;
44: const PetscReal dt = Tf / 8;
45: const PetscReal eps = 100 * PETSC_MACHINE_EPSILON;
46: TSAdapt adapt;
47: PetscInt step;
48: TSConvergedReason reason;
50: PetscFunctionBeginUser;
51: PetscCall(TSGetType(ts, &type));
52: PetscCall(TSGetSolution(ts, &U));
53: PetscCall(VecZeroEntries(U));
54: PetscCall(TSSetStepNumber(ts, 0));
55: PetscCall(TSSetTime(ts, 0));
56: PetscCall(TSSetTimeStep(ts, dt));
57: PetscCall(TSSetMaxTime(ts, Tf));
58: PetscCall(TSSetExactFinalTime(ts, TS_EXACTFINALTIME_MATCHSTEP));
59: PetscCall(TSSolve(ts, NULL));
60: PetscCall(TSRollBack(ts));
61: PetscCall(TSSolve(ts, NULL));
62: PetscCall(TSGetTime(ts, &t));
64: PetscCall(TSGetSolution(ts, &U));
65: PetscCall(VecDuplicate(U, &X));
66: PetscCall(TSEvaluateStep(ts, order, X, NULL));
67: PetscCall(VecGetArrayRead(X, &xx));
68: for (i = 0; i < order; i++) {
69: PetscReal error = PetscAbsReal(PetscRealPart(xx[i]) - PetscPowReal(t, i + 1));
70: PetscCheck(error <= eps, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Bad solution, error %g, %s '%s'", (double)error, type, subtype);
71: }
72: PetscCall(VecRestoreArrayRead(X, &xx));
73: PetscCall(VecDestroy(&X));
75: PetscCall(TSGetSolution(ts, &U));
76: PetscCall(VecDuplicate(U, &Y));
77: PetscCall(TSEvaluateStep(ts, order - 1, Y, &done));
78: PetscCall(VecGetArrayRead(Y, &yy));
79: for (i = 0; done && i < order - 1; i++) {
80: PetscReal error = PetscAbsReal(PetscRealPart(yy[i]) - PetscPowReal(t, i + 1));
81: PetscCheck(error <= eps, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Bad estimator, error %g, %s '%s'", (double)error, type, subtype);
82: }
83: PetscCall(VecRestoreArrayRead(Y, &yy));
84: PetscCall(VecDestroy(&Y));
86: PetscCall(TSGetAdapt(ts, &adapt));
87: PetscCall(TSAdaptSetCheckStage(adapt, TestCheckStage));
88: PetscCall(TSSetErrorIfStepFails(ts, PETSC_FALSE));
89: PetscCall(TSSetStepNumber(ts, 0));
90: PetscCall(TSSetTime(ts, 0));
91: PetscCall(TSSetTimeStep(ts, dt));
92: PetscCall(TSSolve(ts, NULL));
93: PetscCall(TSAdaptSetCheckStage(adapt, NULL));
94: PetscCall(TSSetErrorIfStepFails(ts, PETSC_TRUE));
95: PetscCall(TSGetStepNumber(ts, &step));
96: PetscCall(TSGetConvergedReason(ts, &reason));
97: PetscCheck(step == 2, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Bad step number %" PetscInt_FMT ", %s '%s'", step, type, subtype);
98: PetscCheck(reason == TS_DIVERGED_STEP_REJECTED, PETSC_COMM_SELF, PETSC_ERR_PLIB, "Bad reason %s, %s '%s'", TSConvergedReasons[reason], type, subtype);
99: PetscFunctionReturn(PETSC_SUCCESS);
100: }
102: static PetscErrorCode TestTSRK(TS ts, TSRKType type)
103: {
104: PetscInt order;
105: TSAdapt adapt;
106: PetscBool rk1, rk3, rk4;
107: TSAdaptType adapttype;
108: char savetype[32];
110: PetscFunctionBeginUser;
111: PetscCall(TSRKSetType(ts, type));
112: PetscCall(TSRKGetType(ts, &type));
113: PetscCall(TSRKGetOrder(ts, &order));
115: PetscCall(TSGetAdapt(ts, &adapt));
116: PetscCall(TSAdaptGetType(adapt, &adapttype));
117: PetscCall(PetscStrncpy(savetype, adapttype, sizeof(savetype)));
118: PetscCall(PetscStrcmp(type, TSRK1FE, &rk1));
119: PetscCall(PetscStrcmp(type, TSRK3, &rk3));
120: PetscCall(PetscStrcmp(type, TSRK4, &rk4));
121: if (rk1 || rk3 || rk4) PetscCall(TSAdaptSetType(adapt, TSADAPTNONE));
123: PetscCall(TestExplicitTS(ts, order, type));
125: PetscCall(TSGetAdapt(ts, &adapt));
126: PetscCall(TSAdaptSetType(adapt, savetype));
127: PetscFunctionReturn(PETSC_SUCCESS);
128: }
130: int main(int argc, char *argv[])
131: {
132: TS ts;
133: Vec X;
134: PetscInt N = 9;
136: PetscFunctionBeginUser;
137: PetscCall(PetscInitialize(&argc, &argv, NULL, help));
139: PetscCall(TSCreate(PETSC_COMM_SELF, &ts));
140: PetscCall(TSSetType(ts, TSRK));
141: PetscCall(TSSetRHSFunction(ts, NULL, RHSFunction, NULL));
142: PetscCall(VecCreateSeq(PETSC_COMM_SELF, N, &X));
143: PetscCall(TSSetSolution(ts, X));
144: PetscCall(VecDestroy(&X));
145: PetscCall(TSSetFromOptions(ts));
147: PetscCall(TestTSRK(ts, TSRK1FE));
148: PetscCall(TestTSRK(ts, TSRK2A));
149: PetscCall(TestTSRK(ts, TSRK3));
150: PetscCall(TestTSRK(ts, TSRK3BS));
151: PetscCall(TestTSRK(ts, TSRK4));
152: PetscCall(TestTSRK(ts, TSRK5F));
153: PetscCall(TestTSRK(ts, TSRK5DP));
154: PetscCall(TestTSRK(ts, TSRK5BS));
155: PetscCall(TestTSRK(ts, TSRK6VR));
156: PetscCall(TestTSRK(ts, TSRK7VR));
157: PetscCall(TestTSRK(ts, TSRK8VR));
159: PetscCall(TSRollBack(ts));
160: PetscCall(TSDestroy(&ts));
162: PetscCall(PetscFinalize());
163: return 0;
164: }
166: /*TEST
168: testset:
169: output_file: output/ex14.out
170: test:
171: suffix: 0
172: requires: !single
173: test:
174: suffix: 1
175: args: -ts_adapt_type none
176: test:
177: suffix: 2
178: requires: !single
179: args: -ts_adapt_type basic
180: test:
181: suffix: 3
182: args: -ts_adapt_type dsp
184: TEST*/