xref: /petsc/src/sys/classes/random/impls/sprng/sprng.c (revision 267267bdcbfbae225216e8078da17f7ca9d5f149)
15c6c1daeSBarry Smith 
2d6cc7855SJacob Faibussowitsch #include <petsc/private/randomimpl.h>
35c6c1daeSBarry Smith 
45c6c1daeSBarry Smith #define USE_MPI
55c6c1daeSBarry Smith #define SIMPLE_SPRNG
65c6c1daeSBarry Smith EXTERN_C_BEGIN
75c6c1daeSBarry Smith #include <sprng.h>
85c6c1daeSBarry Smith EXTERN_C_END
95c6c1daeSBarry Smith 
105c6c1daeSBarry Smith PetscErrorCode  PetscRandomSeed_Sprng(PetscRandom r)
115c6c1daeSBarry Smith {
125c6c1daeSBarry Smith   PetscFunctionBegin;
135c6c1daeSBarry Smith   init_sprng(r->seed,SPRNG_DEFAULT);
145c6c1daeSBarry Smith   PetscFunctionReturn(0);
155c6c1daeSBarry Smith }
165c6c1daeSBarry Smith 
175c6c1daeSBarry Smith PetscErrorCode  PetscRandomGetValue_Sprng(PetscRandom r,PetscScalar *val)
185c6c1daeSBarry Smith {
195c6c1daeSBarry Smith   PetscFunctionBegin;
205c6c1daeSBarry Smith #if defined(PETSC_USE_COMPLEX)
215c6c1daeSBarry Smith   if (r->iset) {
22b0043f70SBarry Smith     *val = PetscRealPart(r->width)*sprng() + PetscRealPart(r->low) + (PetscImaginaryPart(r->width)*sprng() + PetscImaginaryPart(r->low)) * PETSC_i;
235c6c1daeSBarry Smith   } else {
245c6c1daeSBarry Smith     *val = sprng() + sprng()*PETSC_i;
255c6c1daeSBarry Smith   }
265c6c1daeSBarry Smith #else
275c6c1daeSBarry Smith   if (r->iset) *val = r->width * sprng() + r->low;
285c6c1daeSBarry Smith   else         *val = sprng();
295c6c1daeSBarry Smith #endif
305c6c1daeSBarry Smith   PetscFunctionReturn(0);
315c6c1daeSBarry Smith }
325c6c1daeSBarry Smith 
334d1a973fSToby Isaac PetscErrorCode  PetscRandomGetValueReal_Sprng(PetscRandom r,PetscReal *val)
345c6c1daeSBarry Smith {
355c6c1daeSBarry Smith   PetscFunctionBegin;
365c6c1daeSBarry Smith #if defined(PETSC_USE_COMPLEX)
375c6c1daeSBarry Smith   if (r->iset) *val = PetscRealPart(r->width)*sprng() + PetscRealPart(r->low);
385c6c1daeSBarry Smith   else         *val = sprng();
395c6c1daeSBarry Smith #else
405c6c1daeSBarry Smith   if (r->iset) *val = r->width * sprng() + r->low;
415c6c1daeSBarry Smith   else         *val = sprng();
425c6c1daeSBarry Smith #endif
435c6c1daeSBarry Smith   PetscFunctionReturn(0);
445c6c1daeSBarry Smith }
455c6c1daeSBarry Smith 
465c6c1daeSBarry Smith static struct _PetscRandomOps PetscRandomOps_Values = {
47*267267bdSJacob Faibussowitsch   PetscDesignatedInitializer(seed,PetscRandomSeed_Sprng),
48*267267bdSJacob Faibussowitsch   PetscDesignatedInitializer(getvalue,PetscRandomGetValue_Sprng),
49*267267bdSJacob Faibussowitsch   PetscDesignatedInitializer(getvaluereal,PetscRandomGetValueReal_Sprng),
505c6c1daeSBarry Smith };
515c6c1daeSBarry Smith 
525c6c1daeSBarry Smith /*MC
535c6c1daeSBarry Smith    PETSCSPRNG- access to the publically available random number generator sprng
545c6c1daeSBarry Smith 
555c6c1daeSBarry Smith    Options Database Keys:
565c6c1daeSBarry Smith . -random_type <rand,rand48,sprng>
575c6c1daeSBarry Smith 
585c6c1daeSBarry Smith   Level: beginner
595c6c1daeSBarry Smith 
605c6c1daeSBarry Smith    PETSc must have been ./configure with the option --download-sprng to use
615c6c1daeSBarry Smith    this random number generator.
625c6c1daeSBarry Smith 
635c6c1daeSBarry Smith    This is NOT currently using a parallel random number generator. Sprng does have
645c6c1daeSBarry Smith    an MPI version we should investigate.
655c6c1daeSBarry Smith 
665c6c1daeSBarry Smith .seealso: RandomCreate(), RandomSetType(), PETSCRAND, PETSCRAND48
675c6c1daeSBarry Smith M*/
685c6c1daeSBarry Smith 
698cc058d9SJed Brown PETSC_EXTERN PetscErrorCode PetscRandomCreate_Sprng(PetscRandom r)
705c6c1daeSBarry Smith {
715c6c1daeSBarry Smith   PetscErrorCode ierr;
725c6c1daeSBarry Smith 
735c6c1daeSBarry Smith   PetscFunctionBegin;
745c6c1daeSBarry Smith   ierr = PetscMemcpy(r->ops,&PetscRandomOps_Values,sizeof(PetscRandomOps_Values));CHKERRQ(ierr);
755c6c1daeSBarry Smith   ierr = PetscObjectChangeTypeName((PetscObject)r,PETSCSPRNG);CHKERRQ(ierr);
765c6c1daeSBarry Smith   PetscFunctionReturn(0);
775c6c1daeSBarry Smith }
78