Actual source code: sprng.c


  2: #include <petsc/private/randomimpl.h>

  4: #define USE_MPI
  5: #define SIMPLE_SPRNG
  6: EXTERN_C_BEGIN
  7: #include <sprng.h>
  8: EXTERN_C_END

 10: PetscErrorCode PetscRandomSeed_Sprng(PetscRandom r)
 11: {
 12:   init_sprng(r->seed, SPRNG_DEFAULT);
 13:   return 0;
 14: }

 16: PetscErrorCode PetscRandomGetValue_Sprng(PetscRandom r, PetscScalar *val)
 17: {
 18: #if defined(PETSC_USE_COMPLEX)
 19:   if (r->iset) {
 20:     *val = PetscRealPart(r->width) * sprng() + PetscRealPart(r->low) + (PetscImaginaryPart(r->width) * sprng() + PetscImaginaryPart(r->low)) * PETSC_i;
 21:   } else {
 22:     *val = sprng() + sprng() * PETSC_i;
 23:   }
 24: #else
 25:   if (r->iset) *val = r->width * sprng() + r->low;
 26:   else *val = sprng();
 27: #endif
 28:   return 0;
 29: }

 31: PetscErrorCode PetscRandomGetValueReal_Sprng(PetscRandom r, PetscReal *val)
 32: {
 33: #if defined(PETSC_USE_COMPLEX)
 34:   if (r->iset) *val = PetscRealPart(r->width) * sprng() + PetscRealPart(r->low);
 35:   else *val = sprng();
 36: #else
 37:   if (r->iset) *val = r->width * sprng() + r->low;
 38:   else *val = sprng();
 39: #endif
 40:   return 0;
 41: }

 43: static struct _PetscRandomOps PetscRandomOps_Values = {
 44:   PetscDesignatedInitializer(seed, PetscRandomSeed_Sprng),
 45:   PetscDesignatedInitializer(getvalue, PetscRandomGetValue_Sprng),
 46:   PetscDesignatedInitializer(getvaluereal, PetscRandomGetValueReal_Sprng),
 47: };

 49: /*MC
 50:    PETSCSPRNG - access to the publicly available random number generator sprng

 52:    Options Database Keys:
 53: . -random_type <rand,rand48,sprng> - select the random number generator at runtime

 55:    Note:
 56:    PETSc must be ./configure with the option --download-sprng to use this random number generator.

 58:    Developer Note:
 59:    This is NOT currently using a parallel random number generator. Sprng does have
 60:    an MPI version we should investigate.

 62:   Level: beginner

 64: .seealso: `RandomCreate()`, `RandomSetType()`, `PETSCRAND`, `PETSCRAND48`, `PetscRandomSetFromOptions()`
 65: M*/

 67: PETSC_EXTERN PetscErrorCode PetscRandomCreate_Sprng(PetscRandom r)
 68: {
 69:   PetscMemcpy(r->ops, &PetscRandomOps_Values, sizeof(PetscRandomOps_Values));
 70:   PetscObjectChangeTypeName((PetscObject)r, PETSCSPRNG);
 71:   return 0;
 72: }