1 #define PETSC_DESIRE_FEATURE_TEST_MACROS /* for drand48() */ 2 #include <../src/sys/classes/random/randomimpl.h> 3 4 PetscErrorCode PetscRandomSeed_Rand48(PetscRandom r) 5 { 6 PetscFunctionBegin; 7 srand48(r->seed); 8 PetscFunctionReturn(0); 9 } 10 11 PetscErrorCode PetscRandomGetValue_Rand48(PetscRandom r,PetscScalar *val) 12 { 13 PetscFunctionBegin; 14 #if defined(PETSC_USE_COMPLEX) 15 if (r->iset) { 16 *val = PetscRealPart(r->width)*(PetscReal)drand48() + PetscRealPart(r->low) + (PetscImaginaryPart(r->width)*(PetscReal)drand48() + PetscImaginaryPart(r->low)) * PETSC_i; 17 } else { 18 *val = (PetscReal)drand48() + (PetscReal)drand48()*PETSC_i; 19 } 20 #else 21 if (r->iset) *val = r->width * drand48() + r->low; 22 else *val = drand48(); 23 #endif 24 PetscFunctionReturn(0); 25 } 26 27 PetscErrorCode PetscRandomGetValueReal_Rand48(PetscRandom r,PetscReal *val) 28 { 29 PetscFunctionBegin; 30 #if defined(PETSC_USE_COMPLEX) 31 if (r->iset) *val = PetscRealPart(r->width)*drand48() + PetscRealPart(r->low); 32 else *val = drand48(); 33 #else 34 if (r->iset) *val = r->width * drand48() + r->low; 35 else *val = drand48(); 36 #endif 37 PetscFunctionReturn(0); 38 } 39 40 static struct _PetscRandomOps PetscRandomOps_Values = { 41 /* 0 */ 42 PetscRandomSeed_Rand48, 43 PetscRandomGetValue_Rand48, 44 PetscRandomGetValueReal_Rand48, 45 NULL, 46 /* 5 */ 47 NULL 48 }; 49 50 /*MC 51 PETSCRAND48 - access to the basic Unix drand48() random number generator 52 53 Options Database Keys: 54 . -random_type <rand,rand48,sprng> 55 56 Level: beginner 57 58 .seealso: RandomCreate(), RandomSetType(), PETSCRAND, PETSCSPRNG 59 M*/ 60 61 PETSC_EXTERN PetscErrorCode PetscRandomCreate_Rand48(PetscRandom r) 62 { 63 PetscErrorCode ierr; 64 65 PetscFunctionBegin; 66 ierr = PetscMemcpy(r->ops,&PetscRandomOps_Values,sizeof(PetscRandomOps_Values));CHKERRQ(ierr); 67 ierr = PetscObjectChangeTypeName((PetscObject)r,PETSCRAND48);CHKERRQ(ierr); 68 PetscFunctionReturn(0); 69 } 70