xref: /petsc/src/ts/tests/ex14.c (revision c87ba875e4007ad659b117ea274f03d5f4cd5ea7)
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   PetscErrorCode    ierr;
11 
12   PetscFunctionBegin;
13   ierr = VecGetLocalSize(X,&n);CHKERRQ(ierr);
14   ierr = VecGetArrayRead(X,&xx);CHKERRQ(ierr);
15   ierr = VecGetArray(F,&ff);CHKERRQ(ierr);
16 
17   if (n >= 1)
18     ff[0] = 1;
19   for (i = 1; i < n; i++)
20     ff[i] = (i+1)*(xx[i-1]+PetscPowReal(t,i))/2;
21 
22   ierr = VecRestoreArrayRead(X,&xx);CHKERRQ(ierr);
23   ierr = VecRestoreArray(F,&ff);CHKERRQ(ierr);
24   PetscFunctionReturn(0);
25 }
26 
27 PetscErrorCode TestCheckStage(TSAdapt adapt,TS ts,PetscReal t,Vec X,PetscBool *accept)
28 {
29   PetscInt       step;
30   PetscErrorCode ierr;
31 
32   PetscFunctionBegin;
33   ierr = TSGetStepNumber(ts,&step);CHKERRQ(ierr);
34   *accept = (step >= 2) ? PETSC_FALSE : PETSC_TRUE;
35   PetscFunctionReturn(0);
36 }
37 
38 static PetscErrorCode TestExplicitTS(TS ts,PetscInt order,const char subtype[])
39 {
40   PetscInt          i;
41   PetscReal         t;
42   Vec               U,X,Y;
43   TSType            type;
44   PetscBool         done;
45   const PetscScalar *xx;
46   const PetscScalar *yy;
47   const PetscReal   Tf  = 1;
48   const PetscReal   dt  = Tf/8;
49   const PetscReal   eps = 100*PETSC_MACHINE_EPSILON;
50   TSAdapt           adapt;
51   PetscInt          step;
52   TSConvergedReason reason;
53   PetscErrorCode    ierr;
54 
55   PetscFunctionBegin;
56   ierr = TSGetType(ts,&type);CHKERRQ(ierr);
57   ierr = TSGetSolution(ts,&U);CHKERRQ(ierr);
58   ierr = VecZeroEntries(U);CHKERRQ(ierr);
59   ierr = TSSetStepNumber(ts,0);CHKERRQ(ierr);
60   ierr = TSSetTime(ts,0);CHKERRQ(ierr);
61   ierr = TSSetTimeStep(ts,dt);CHKERRQ(ierr);
62   ierr = TSSetMaxTime(ts,Tf);CHKERRQ(ierr);
63   ierr = TSSetExactFinalTime(ts,TS_EXACTFINALTIME_MATCHSTEP);CHKERRQ(ierr);
64   ierr = TSSolve(ts,NULL);CHKERRQ(ierr);
65   ierr = TSGetTime(ts,&t);CHKERRQ(ierr);
66 
67   ierr = TSGetSolution(ts,&U);CHKERRQ(ierr);
68   ierr = VecDuplicate(U,&X);CHKERRQ(ierr);
69   ierr = TSEvaluateStep(ts,order,X,NULL);CHKERRQ(ierr);
70   ierr = VecGetArrayRead(X,&xx);CHKERRQ(ierr);
71   for (i = 0; i < order; i++) {
72     PetscReal error = PetscAbsReal(PetscRealPart(xx[i]) - PetscPowReal(t,i+1));
73     if (error > eps) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad solution, error %g, %s '%s'",(double)error,type,subtype);
74   }
75   ierr = VecRestoreArrayRead(X,&xx);CHKERRQ(ierr);
76   ierr = VecDestroy(&X);CHKERRQ(ierr);
77 
78   ierr = TSGetSolution(ts,&U);CHKERRQ(ierr);
79   ierr = VecDuplicate(U,&Y);CHKERRQ(ierr);
80   ierr = TSEvaluateStep(ts,order-1,Y,&done);CHKERRQ(ierr);
81   ierr = VecGetArrayRead(Y,&yy);CHKERRQ(ierr);
82   for (i = 0; done && i < order-1; i++) {
83     PetscReal error = PetscAbsReal(PetscRealPart(yy[i]) - PetscPowReal(t,i+1));
84     if (error > eps) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad estimator, error %g, %s '%s'",(double)error,type,subtype);
85   }
86   ierr = VecRestoreArrayRead(Y,&yy);CHKERRQ(ierr);
87   ierr = VecDestroy(&Y);CHKERRQ(ierr);
88 
89   ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr);
90   ierr = TSAdaptSetCheckStage(adapt,TestCheckStage);CHKERRQ(ierr);
91   ierr = TSSetErrorIfStepFails(ts,PETSC_FALSE);CHKERRQ(ierr);
92   ierr = TSSetStepNumber(ts,0);CHKERRQ(ierr);
93   ierr = TSSetTime(ts,0);CHKERRQ(ierr);
94   ierr = TSSetTimeStep(ts,dt);CHKERRQ(ierr);
95   ierr = TSSolve(ts,NULL);CHKERRQ(ierr);
96   ierr = TSAdaptSetCheckStage(adapt,NULL);CHKERRQ(ierr);
97   ierr = TSSetErrorIfStepFails(ts,PETSC_TRUE);CHKERRQ(ierr);
98   ierr = TSGetStepNumber(ts,&step);CHKERRQ(ierr);
99   ierr = TSGetConvergedReason(ts,&reason);CHKERRQ(ierr);
100   if (step != 2) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad step number %D, %s '%s'",step,type,subtype);
101   if (reason != TS_DIVERGED_STEP_REJECTED) SETERRQ3(PETSC_COMM_SELF,PETSC_ERR_PLIB,"Bad reason %s, %s '%s'",TSConvergedReasons[reason],type,subtype);
102   PetscFunctionReturn(0);
103 }
104 
105 static PetscErrorCode TestTSRK(TS ts,TSRKType type)
106 {
107   PetscInt       order;
108   TSAdapt        adapt;
109   PetscBool      rk1,rk3,rk4;
110   TSAdaptType    adapttype;
111   char           savetype[32];
112   PetscErrorCode ierr;
113 
114   PetscFunctionBegin;
115   ierr = TSRKSetType(ts,type);CHKERRQ(ierr);
116   ierr = TSRKGetType(ts,&type);CHKERRQ(ierr);
117   ierr = TSRKGetOrder(ts,&order);CHKERRQ(ierr);
118 
119   ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr);
120   ierr = TSAdaptGetType(adapt,&adapttype);CHKERRQ(ierr);
121   ierr = PetscStrncpy(savetype,adapttype,sizeof(savetype));CHKERRQ(ierr);
122   ierr = PetscStrcmp(type,TSRK1FE,&rk1);CHKERRQ(ierr);
123   ierr = PetscStrcmp(type,TSRK3,&rk3);CHKERRQ(ierr);
124   ierr = PetscStrcmp(type,TSRK4,&rk4);CHKERRQ(ierr);
125   if (rk1 || rk3 || rk4) {ierr = TSAdaptSetType(adapt,TSADAPTNONE);CHKERRQ(ierr);}
126 
127   ierr = TestExplicitTS(ts,order,type);CHKERRQ(ierr);
128 
129   ierr = TSGetAdapt(ts,&adapt);CHKERRQ(ierr);
130   ierr = TSAdaptSetType(adapt,savetype);CHKERRQ(ierr);
131   PetscFunctionReturn(0);
132 }
133 
134 int main(int argc, char *argv[])
135 {
136   TS             ts;
137   Vec            X;
138   PetscInt       N = 9;
139   PetscErrorCode ierr;
140 
141   ierr = PetscInitialize(&argc,&argv,NULL,help);if (ierr) return ierr;
142 
143   ierr = TSCreate(PETSC_COMM_SELF,&ts);CHKERRQ(ierr);
144   ierr = TSSetType(ts,TSRK);CHKERRQ(ierr);
145   ierr = TSSetRHSFunction(ts,NULL,RHSFunction,NULL);CHKERRQ(ierr);
146   ierr = VecCreateSeq(PETSC_COMM_SELF,N,&X);CHKERRQ(ierr);
147   ierr = TSSetSolution(ts,X);CHKERRQ(ierr);
148   ierr = VecDestroy(&X);CHKERRQ(ierr);
149   ierr = TSSetFromOptions(ts);CHKERRQ(ierr);
150 
151   ierr = TestTSRK(ts,TSRK1FE);CHKERRQ(ierr);
152   ierr = TestTSRK(ts,TSRK2A);CHKERRQ(ierr);
153   ierr = TestTSRK(ts,TSRK3);CHKERRQ(ierr);
154   ierr = TestTSRK(ts,TSRK3BS);CHKERRQ(ierr);
155   ierr = TestTSRK(ts,TSRK4);CHKERRQ(ierr);
156   ierr = TestTSRK(ts,TSRK5F);CHKERRQ(ierr);
157   ierr = TestTSRK(ts,TSRK5DP);CHKERRQ(ierr);
158   ierr = TestTSRK(ts,TSRK5BS);CHKERRQ(ierr);
159   ierr = TestTSRK(ts,TSRK6VR);CHKERRQ(ierr);
160   ierr = TestTSRK(ts,TSRK7VR);CHKERRQ(ierr);
161   ierr = TestTSRK(ts,TSRK8VR);CHKERRQ(ierr);
162 
163   ierr = TSRollBack(ts);CHKERRQ(ierr);
164   ierr = TSDestroy(&ts);CHKERRQ(ierr);
165 
166   ierr = PetscFinalize();
167   return ierr;
168 }
169 
170 /*TEST
171 
172 testset:
173   output_file: output/ex14.out
174   test:
175     suffix: 0
176   test:
177     suffix: 1
178     args: -ts_adapt_type none
179   test:
180     suffix: 2
181     args: -ts_adapt_type basic
182   test:
183     suffix: 3
184     args: -ts_adapt_type dsp
185 
186 TEST*/
187