Date: 2013-07-02T14:38:35+00:00

Actual source code: rand48.c
petsc-3.4.2 2013-07-02

      2: #include <../src/sys/classes/random/randomimpl.h>

      6: PetscErrorCode  PetscRandomSeed_Rand48(PetscRandom r)
      7: {
      9:   srand48(r->seed);
     10:   return(0);
     11: }

     15: PetscErrorCode  PetscRandomGetValue_Rand48(PetscRandom r,PetscScalar *val)
     16: {
     18: #if defined(PETSC_USE_COMPLEX)
     19:   if (r->iset) {
     20:     *val = PetscRealPart(r->width)*(PetscReal)drand48() + PetscRealPart(r->low) + (PetscImaginaryPart(r->width)*(PetscReal)drand48() + PetscImaginaryPart(r->low)) * PETSC_i;
     21:   } else {
     22:     *val = (PetscReal)drand48() + (PetscReal)drand48()*PETSC_i;
     23:   }
     24: #else
     25:   if (r->iset) *val = r->width * drand48() + r->low;
     26:   else         *val = drand48();
     27: #endif
     28:   return(0);
     29: }

     33: PetscErrorCode  PetscRandomGetValueReal_Rand48(PetscRandom r,PetscReal *val)
     34: {
     36: #if defined(PETSC_USE_COMPLEX)
     37:   if (r->iset) *val = PetscRealPart(r->width)*drand48() + PetscRealPart(r->low);
     38:   else         *val = drand48();
     39: #else
     40:   if (r->iset) *val = r->width * drand48() + r->low;
     41:   else         *val = drand48();
     42: #endif
     43:   return(0);
     44: }

     46: static struct _PetscRandomOps PetscRandomOps_Values = {
     47:   /* 0 */
     48:   PetscRandomSeed_Rand48,
     49:   PetscRandomGetValue_Rand48,
     50:   PetscRandomGetValueReal_Rand48,
     51:   0,
     52:   /* 5 */
     53:   0
     54: };

     56: /*MC
     57:    PETSCRAND48 - access to the basic Unix drand48() random number generator

     59:    Options Database Keys:
     60: . -random_type <rand,rand48,sprng>

     62:   Level: beginner

     64: .seealso: RandomCreate(), RandomSetType(), PETSCRAND, PETSCSPRNG
     65: M*/

     69: PETSC_EXTERN PetscErrorCode PetscRandomCreate_Rand48(PetscRandom r)
     70: {

     74:   PetscMemcpy(r->ops,&PetscRandomOps_Values,sizeof(PetscRandomOps_Values));
     75:   PetscObjectChangeTypeName((PetscObject)r,PETSCRAND48);
     76:   return(0);
     77: }