Actual source code: ex5.c
1: static char help[] = "Demonstrates using the PetscBag Object\n\n";
3: #include <petscsys.h>
4: #include <petscbag.h>
5: #include <petscviewer.h>
7: /*
8: Enum variables can be stored in a bag but require a string array
9: to name their fields. The fourth entry in this example is the name
10: of the enum, the fifth is the prefix (none in this case), and the last
11: entry is the null string.
12: */
13: typedef enum {
14: THIS = 0,
15: THAT = 1,
16: THE_OTHER = 2
17: } YourChoice;
18: const char *EnumeratedChoices[] = {"THIS", "THAT", "THE_OTHER", "EnumeratedChoices", "", 0};
20: /*
21: Data structures can be used in a bag as long as they
22: are declared in the bag with a variable, not with a pointer.
23: */
24: typedef struct {
25: PetscReal x1, x2;
26: } TwoVec;
28: /*
29: Define a C struct that will contain my program's parameters.
31: A PETSc bag is merely a representation of a C struct that can be printed, saved to a file and loaded from a file.
32: */
33: typedef struct {
34: PetscScalar W;
35: PetscReal rho;
36: TwoVec pos;
37: PetscInt Ii;
38: PetscInt iarray[3];
39: PetscReal rarray[2];
40: PetscBool T;
41: PetscBool Tarray[3];
42: PetscDataType dt;
43: char filename[PETSC_MAX_PATH_LEN];
44: YourChoice which;
45: } Parameter;
47: int main(int argc, char **argv)
48: {
49: PetscBag bag;
50: Parameter *params;
51: PetscViewer viewer;
52: PetscBool flg;
53: char filename[PETSC_MAX_PATH_LEN] = "binaryoutput";
55: /*
56: Every PETSc routine should begin with the PetscInitialize() routine.
57: argc, argv - These command line arguments are taken to extract the options
58: supplied to PETSc and options supplied to MPI.
59: help - When PETSc executable is invoked with the option -help,
60: it prints the various options that can be applied at
61: runtime. The user can use the "help" variable place
62: additional help messages in this printout.
63: */
64: PetscFunctionBeginUser;
65: PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
67: /* Create an empty bag */
68: PetscCall(PetscBagCreate(PETSC_COMM_WORLD, sizeof(Parameter), &bag));
69: PetscCall(PetscBagGetData(bag, (void **)¶ms));
71: /* register variables, defaults, names, help strings */
72: PetscCall(PetscBagSetName(bag, "ParameterBag", "contains parameters for simulations of top-secret, dangerous physics"));
73: PetscCall(PetscBagSetOptionsPrefix(bag, "pbag_"));
74: PetscCall(PetscBagRegisterString(bag, ¶ms->filename, PETSC_MAX_PATH_LEN, "myfile", "filename", "Name of secret file"));
75: PetscCall(PetscBagRegisterReal(bag, ¶ms->rho, 3.0, "rho", "Density, kg/m^3"));
76: PetscCall(PetscBagRegisterScalar(bag, ¶ms->W, 5.0, "W", "Vertical velocity, m/sec"));
77: PetscCall(PetscBagRegisterInt(bag, ¶ms->Ii, 2, "modes_x", "Number of modes in x-direction"));
79: params->iarray[0] = 1;
80: params->iarray[1] = 2;
81: params->iarray[2] = 3;
83: PetscCall(PetscBagRegisterIntArray(bag, ¶ms->iarray, 3, "int_array", "Int array with 3 locations"));
85: params->rarray[0] = -1.0;
86: params->rarray[1] = -2.0;
88: PetscCall(PetscBagRegisterRealArray(bag, ¶ms->rarray, 2, "real_array", "Real array with 2 locations"));
89: PetscCall(PetscBagRegisterBool(bag, ¶ms->T, PETSC_FALSE, "do_output", "Write output file (yes/no)"));
90: PetscCall(PetscBagRegisterBoolArray(bag, ¶ms->Tarray, 3, "bool_array", "Bool array with 3 locations"));
91: PetscCall(PetscBagRegisterEnum(bag, ¶ms->dt, PetscDataTypes, (PetscEnum)PETSC_INT, "dt", "meaningless datatype"));
92: PetscCall(PetscBagRegisterReal(bag, ¶ms->pos.x1, 1.0, "x1", "x position"));
93: PetscCall(PetscBagRegisterReal(bag, ¶ms->pos.x2, 1.9, "x2", "y position"));
94: PetscCall(PetscBagRegisterEnum(bag, ¶ms->which, EnumeratedChoices, (PetscEnum)THAT, "choose", "Express yourself by choosing among enumerated things"));
96: /* This option allows loading user-provided PetscBag */
97: PetscCall(PetscOptionsGetString(NULL, NULL, "-f", filename, sizeof(filename), &flg));
98: if (!flg) {
99: /* write bag to stdio & binary file */
100: PetscCall(PetscBagView(bag, PETSC_VIEWER_STDOUT_WORLD));
101: PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, filename, FILE_MODE_WRITE, &viewer));
102: PetscCall(PetscBagView(bag, viewer));
103: PetscCall(PetscViewerDestroy(&viewer));
104: }
106: PetscCall(PetscMemzero(params, sizeof(Parameter)));
108: /* load bag from file & write to stdio */
109: PetscCall(PetscViewerBinaryOpen(PETSC_COMM_WORLD, filename, FILE_MODE_READ, &viewer));
110: PetscCall(PetscBagLoad(viewer, bag));
111: PetscCall(PetscViewerDestroy(&viewer));
112: PetscCall(PetscBagSetFromOptions(bag));
113: PetscCall(PetscBagView(bag, PETSC_VIEWER_STDOUT_WORLD));
115: /* reuse the parameter struct */
116: PetscCall(PetscBagGetData(bag, (void **)¶ms));
117: PetscCall(PetscPrintf(PETSC_COMM_WORLD, "The value of rho after loading is: %f\n", (double)params->rho));
119: /* clean up and exit */
120: PetscCall(PetscBagDestroy(&bag));
121: PetscCall(PetscFinalize());
122: return 0;
123: }
125: /*TEST
127: test:
128: args: -pbag_rho 44 -pbag_do_output true
129: requires: !complex
131: test:
132: suffix: yaml
133: requires: !complex
134: args: -options_file bag.yml -options_view
135: filter: grep -E -v "(options_view)"
136: localrunfiles: bag.yml
138: TEST*/