xref: /petsc/src/ts/tests/ex14.c (revision 40badf4fbc550ac1f60bd080eaff6de6d55b946d)
1 static char help[] ="Tests all TSRK types \n\n";
2 
3 #include <petscts.h>
4 
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;
10 
11   PetscFunctionBegin;
12   CHKERRQ(VecGetLocalSize(X,&n));
13   CHKERRQ(VecGetArrayRead(X,&xx));
14   CHKERRQ(VecGetArray(F,&ff));
15 
16   if (n >= 1)
17     ff[0] = 1;
18   for (i = 1; i < n; i++)
19     ff[i] = (i+1)*(xx[i-1]+PetscPowReal(t,i))/2;
20 
21   CHKERRQ(VecRestoreArrayRead(X,&xx));
22   CHKERRQ(VecRestoreArray(F,&ff));
23   PetscFunctionReturn(0);
24 }
25 
26 PetscErrorCode TestCheckStage(TSAdapt adapt,TS ts,PetscReal t,Vec X,PetscBool *accept)
27 {
28   PetscInt       step;
29 
30   PetscFunctionBegin;
31   CHKERRQ(TSGetStepNumber(ts,&step));
32   *accept = (step >= 2) ? PETSC_FALSE : PETSC_TRUE;
33   PetscFunctionReturn(0);
34 }
35 
36 static PetscErrorCode TestExplicitTS(TS ts,PetscInt order,const char subtype[])
37 {
38   PetscInt          i;
39   PetscReal         t;
40   Vec               U,X,Y;
41   TSType            type;
42   PetscBool         done;
43   const PetscScalar *xx;
44   const PetscScalar *yy;
45   const PetscReal   Tf  = 1;
46   const PetscReal   dt  = Tf/8;
47   const PetscReal   eps = 100*PETSC_MACHINE_EPSILON;
48   TSAdapt           adapt;
49   PetscInt          step;
50   TSConvergedReason reason;
51 
52   PetscFunctionBegin;
53   CHKERRQ(TSGetType(ts,&type));
54   CHKERRQ(TSGetSolution(ts,&U));
55   CHKERRQ(VecZeroEntries(U));
56   CHKERRQ(TSSetStepNumber(ts,0));
57   CHKERRQ(TSSetTime(ts,0));
58   CHKERRQ(TSSetTimeStep(ts,dt));
59   CHKERRQ(TSSetMaxTime(ts,Tf));
60   CHKERRQ(TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP));
61   CHKERRQ(TSSolve(ts,NULL));
62   CHKERRQ(TSRollBack(ts));
63   CHKERRQ(TSSolve(ts,NULL));
64   CHKERRQ(TSGetTime(ts,&t));
65 
66   CHKERRQ(TSGetSolution(ts,&U));
67   CHKERRQ(VecDuplicate(U,&X));
68   CHKERRQ(TSEvaluateStep(ts,order,X,NULL));
69   CHKERRQ(VecGetArrayRead(X,&xx));
70   for (i = 0; i < order; i++) {
71     PetscReal error = PetscAbsReal(PetscRealPart(xx[i]) - PetscPowReal(t,i+1));
72     PetscCheck(error <= eps,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad solution, error %g, %s '%s'",(double)error,type,subtype);
73   }
74   CHKERRQ(VecRestoreArrayRead(X,&xx));
75   CHKERRQ(VecDestroy(&X));
76 
77   CHKERRQ(TSGetSolution(ts,&U));
78   CHKERRQ(VecDuplicate(U,&Y));
79   CHKERRQ(TSEvaluateStep(ts,order-1,Y,&done));
80   CHKERRQ(VecGetArrayRead(Y,&yy));
81   for (i = 0; done && i < order-1; i++) {
82     PetscReal error = PetscAbsReal(PetscRealPart(yy[i]) - PetscPowReal(t,i+1));
83     PetscCheck(error <= eps,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad estimator, error %g, %s '%s'",(double)error,type,subtype);
84   }
85   CHKERRQ(VecRestoreArrayRead(Y,&yy));
86   CHKERRQ(VecDestroy(&Y));
87 
88   CHKERRQ(TSGetAdapt(ts,&adapt));
89   CHKERRQ(TSAdaptSetCheckStage(adapt,TestCheckStage));
90   CHKERRQ(TSSetErrorIfStepFails(ts,PETSC_FALSE));
91   CHKERRQ(TSSetStepNumber(ts,0));
92   CHKERRQ(TSSetTime(ts,0));
93   CHKERRQ(TSSetTimeStep(ts,dt));
94   CHKERRQ(TSSolve(ts,NULL));
95   CHKERRQ(TSAdaptSetCheckStage(adapt,NULL));
96   CHKERRQ(TSSetErrorIfStepFails(ts,PETSC_TRUE));
97   CHKERRQ(TSGetStepNumber(ts,&step));
98   CHKERRQ(TSGetConvergedReason(ts,&reason));
99   PetscCheck(step == 2,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad step number %D, %s '%s'",step,type,subtype);
100   PetscCheck(reason == TS_DIVERGED_STEP_REJECTED,PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad reason %s, %s '%s'",TSConvergedReasons[reason],type,subtype);
101   PetscFunctionReturn(0);
102 }
103 
104 static PetscErrorCode TestTSRK(TS ts,TSRKType type)
105 {
106   PetscInt       order;
107   TSAdapt        adapt;
108   PetscBool      rk1,rk3,rk4;
109   TSAdaptType    adapttype;
110   char           savetype[32];
111 
112   PetscFunctionBegin;
113   CHKERRQ(TSRKSetType(ts,type));
114   CHKERRQ(TSRKGetType(ts,&type));
115   CHKERRQ(TSRKGetOrder(ts,&order));
116 
117   CHKERRQ(TSGetAdapt(ts,&adapt));
118   CHKERRQ(TSAdaptGetType(adapt,&adapttype));
119   CHKERRQ(PetscStrncpy(savetype,adapttype,sizeof(savetype)));
120   CHKERRQ(PetscStrcmp(type,TSRK1FE,&rk1));
121   CHKERRQ(PetscStrcmp(type,TSRK3,&rk3));
122   CHKERRQ(PetscStrcmp(type,TSRK4,&rk4));
123   if (rk1 || rk3 || rk4) CHKERRQ(TSAdaptSetType(adapt,TSADAPTNONE));
124 
125   CHKERRQ(TestExplicitTS(ts,order,type));
126 
127   CHKERRQ(TSGetAdapt(ts,&adapt));
128   CHKERRQ(TSAdaptSetType(adapt,savetype));
129   PetscFunctionReturn(0);
130 }
131 
132 int main(int argc, char *argv[])
133 {
134   TS             ts;
135   Vec            X;
136   PetscInt       N = 9;
137   PetscErrorCode ierr;
138 
139   ierr = PetscInitialize(&argc,&argv,NULL,help);if (ierr) return ierr;
140 
141   CHKERRQ(TSCreate(PETSC_COMM_SELF,&ts));
142   CHKERRQ(TSSetType(ts,TSRK));
143   CHKERRQ(TSSetRHSFunction(ts,NULL,RHSFunction,NULL));
144   CHKERRQ(VecCreateSeq(PETSC_COMM_SELF,N,&X));
145   CHKERRQ(TSSetSolution(ts,X));
146   CHKERRQ(VecDestroy(&X));
147   CHKERRQ(TSSetFromOptions(ts));
148 
149   CHKERRQ(TestTSRK(ts,TSRK1FE));
150   CHKERRQ(TestTSRK(ts,TSRK2A));
151   CHKERRQ(TestTSRK(ts,TSRK3));
152   CHKERRQ(TestTSRK(ts,TSRK3BS));
153   CHKERRQ(TestTSRK(ts,TSRK4));
154   CHKERRQ(TestTSRK(ts,TSRK5F));
155   CHKERRQ(TestTSRK(ts,TSRK5DP));
156   CHKERRQ(TestTSRK(ts,TSRK5BS));
157   CHKERRQ(TestTSRK(ts,TSRK6VR));
158   CHKERRQ(TestTSRK(ts,TSRK7VR));
159   CHKERRQ(TestTSRK(ts,TSRK8VR));
160 
161   CHKERRQ(TSRollBack(ts));
162   CHKERRQ(TSDestroy(&ts));
163 
164   ierr = PetscFinalize();
165   return ierr;
166 }
167 
168 /*TEST
169 
170 testset:
171   output_file: output/ex14.out
172   test:
173     suffix: 0
174   test:
175     suffix: 1
176     args: -ts_adapt_type none
177   test:
178     suffix: 2
179     args: -ts_adapt_type basic
180   test:
181     suffix: 3
182     args: -ts_adapt_type dsp
183 
184 TEST*/
185