2: static char help[] = "Demonstrates using the PetscBag Object\n\n";

  4: #include <petscsys.h>
  5: #include <petscbag.h>
  6: #include <petscviewer.h>

  8: /*
  9:   Enum variables can be stored in a bag but require a string array
 10:   to name their fields.  The fourth entry in this example is the name
 11:   of the enum, the fifth is the prefix (none in this case), and the last
 12:   entry is the null string.
 13: */
 14: typedef enum {
 15:   THIS = 0, THAT = 1, THE_OTHER = 2
 16: } YourChoice;
 17: const char *EnumeratedChoices[] = {"THIS","THAT","THE_OTHER","EnumeratedChoices","",0};

 19: /*
 20:   Data structures can be used in a bag as long as they
 21:   are declared in the bag with a variable, not with a pointer.
 22: */
 23: typedef struct {
 24:   PetscReal x1,x2;
 25: } TwoVec;

 27: /*
 28:   Define a C struct that will contain my program's parameters.

 30:   A PETSc bag is merely a representation of a C struct that can be printed, saved to a file and loaded from a file.
 31: */
 32: typedef struct {
 33:   PetscScalar   W;
 34:   PetscReal     rho;
 35:   TwoVec        pos;
 36:   PetscInt      Ii;
 37:   PetscInt      iarray[3];
 38:   PetscReal     rarray[2];
 39:   PetscBool     T;
 40:   PetscBool     Tarray[3];
 41:   PetscDataType dt;
 42:   char          filename[PETSC_MAX_PATH_LEN];
 43:   YourChoice    which;
 44: } Parameter;

 46: int main(int argc,char **argv)
 47: {
 48:   PetscBag       bag;
 49:   Parameter      *params;
 50:   PetscViewer    viewer;
 51:   PetscBool      flg;
 52:   char           filename[PETSC_MAX_PATH_LEN] = "binaryoutput";

 54:   /*
 55:     Every PETSc routine should begin with the PetscInitialize() routine.
 56:     argc, argv - These command line arguments are taken to extract the options
 57:                  supplied to PETSc and options supplied to MPI.
 58:     help       - When PETSc executable is invoked with the option -help,
 59:                  it prints the various options that can be applied at
 60:                  runtime.  The user can use the "help" variable place
 61:                  additional help messages in this printout.
 62:   */
 63:   PetscInitialize(&argc,&argv,(char*)0,help);

 65:   /* Create an empty bag */
 66:   PetscBagCreate(PETSC_COMM_WORLD,sizeof(Parameter),&bag);
 67:   PetscBagGetData(bag,(void**)&params);

 69:   /* register variables, defaults, names, help strings */
 70:   PetscBagSetName(bag,"ParameterBag","contains parameters for simulations of top-secret, dangerous physics");
 71:   PetscBagSetOptionsPrefix(bag, "pbag_");
 72:   PetscBagRegisterString(bag,&params->filename,PETSC_MAX_PATH_LEN,"myfile","filename","Name of secret file");
 73:   PetscBagRegisterReal  (bag,&params->rho,3.0,"rho","Density, kg/m^3");
 74:   PetscBagRegisterScalar(bag,&params->W,  5.0,"W","Vertical velocity, m/sec");
 75:   PetscBagRegisterInt   (bag,&params->Ii, 2,"modes_x","Number of modes in x-direction");

 77:   params->iarray[0] = 1;
 78:   params->iarray[1] = 2;
 79:   params->iarray[2] = 3;

 81:   PetscBagRegisterIntArray(bag,&params->iarray, 3,"int_array","Int array with 3 locations");

 83:   params->rarray[0] = -1.0;
 84:   params->rarray[1] = -2.0;

 86:   PetscBagRegisterRealArray(bag,&params->rarray, 2,"real_array","Real array with 2 locations");
 87:   PetscBagRegisterBool (bag,&params->T,  PETSC_FALSE,"do_output","Write output file (yes/no)");
 88:   PetscBagRegisterBoolArray(bag,&params->Tarray, 3,"bool_array","Bool array with 3 locations");
 89:   PetscBagRegisterEnum  (bag,&params->dt, PetscDataTypes,(PetscEnum)PETSC_INT,"dt","meaningless datatype");
 90:   PetscBagRegisterReal  (bag,&params->pos.x1,1.0,"x1","x position");
 91:   PetscBagRegisterReal  (bag,&params->pos.x2,1.9,"x2","y position");
 92:   PetscBagRegisterEnum  (bag,&params->which, EnumeratedChoices, (PetscEnum)THAT, "choose","Express yourself by choosing among enumerated things");

 94:   /* This option allows loading user-provided PetscBag */
 95:   PetscOptionsGetString(NULL,NULL,"-f",filename,sizeof(filename),&flg);
 96:   if (!flg) {

 98:     /* write bag to stdio & binary file */
 99:     PetscBagView(bag,PETSC_VIEWER_STDOUT_WORLD);
100:     PetscViewerBinaryOpen(PETSC_COMM_WORLD,filename,FILE_MODE_WRITE,&viewer);
101:     PetscBagView(bag,viewer);
102:     PetscViewerDestroy(&viewer);
103:   }

105:   PetscMemzero(params,sizeof(Parameter));

107:   /* load bag from file & write to stdio */
108:   PetscViewerBinaryOpen(PETSC_COMM_WORLD,filename,FILE_MODE_READ,&viewer);
109:   PetscBagLoad(viewer,bag);
110:   PetscViewerDestroy(&viewer);
111:   PetscBagSetFromOptions(bag);
112:   PetscBagView(bag,PETSC_VIEWER_STDOUT_WORLD);

114:   /* reuse the parameter struct */
115:   PetscBagGetData(bag,(void**)&params);
116:   PetscPrintf(PETSC_COMM_WORLD,"The value of rho after loading is: %f\n",(double)params->rho);

118:   /* clean up and exit */
119:   PetscBagDestroy(&bag);
120:   PetscFinalize();
121:   return 0;
122: }

124: /*TEST

126:    test:
127:       args: -pbag_rho 44 -pbag_do_output true
128:       requires: !complex

130:    test:
131:       suffix: yaml
132:       requires: !complex
133:       args: -options_file bag.yml -options_view
134:       filter: egrep -v "(options_left|options_view|malloc_dump|malloc_test|saws_port_auto_select|display|check_pointer_intensity|error_output_stdout|nox|vecscatter_mpi1|use_gpu_aware_mpi|checkstack)"
135:       localrunfiles: bag.yml

137: TEST*/