1 2 static char help[] = "Tests PetscRandom functions.\n\n"; 3 4 #include <petscsys.h> 5 6 /* Usage: 7 mpiexec -n <np> ./ex1 -n <num_of_random_numbers> -random_type <type> -log_view 8 -view_randomvalues <view_rank> 9 -random_view ascii -random_view :filename 10 */ 11 12 int main(int argc, char **argv) { 13 PetscInt i, n = 1000, *values; 14 PetscRandom rnd; 15 PetscScalar value, avg = 0.0; 16 PetscMPIInt rank; 17 PetscInt view_rank = -1; 18 #if defined(PETSC_USE_LOG) 19 PetscLogEvent event; 20 #endif 21 22 PetscFunctionBeginUser; 23 PetscCall(PetscInitialize(&argc, &argv, (char *)0, help)); 24 PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank)); 25 PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL)); 26 PetscCall(PetscOptionsGetInt(NULL, NULL, "-view_randomvalues", &view_rank, NULL)); 27 28 PetscCall(PetscRandomCreate(PETSC_COMM_WORLD, &rnd)); 29 /* force imaginary part of random number to always be zero; thus obtain reproducible results with real and complex numbers */ 30 PetscCall(PetscRandomSetInterval(rnd, 0.0, 1.0)); 31 PetscCall(PetscRandomSetFromOptions(rnd)); 32 33 PetscCall(PetscMalloc1(n, &values)); 34 for (i = 0; i < n; i++) { 35 PetscCall(PetscRandomGetValue(rnd, &value)); 36 avg += value; 37 if (view_rank == (PetscInt)rank) PetscCall(PetscPrintf(PETSC_COMM_SELF, "[%d] value[%" PetscInt_FMT "] = %6.4e\n", rank, i, (double)PetscRealPart(value))); 38 values[i] = (PetscInt)(n * PetscRealPart(value) + 2.0); 39 } 40 avg = avg / ((PetscReal)n); 41 if (view_rank == (PetscInt)rank) PetscCall(PetscPrintf(PETSC_COMM_SELF, "[%d] Average value %6.4e\n", rank, (double)PetscRealPart(avg))); 42 43 PetscCall(PetscSortInt(n, values)); 44 45 PetscCall(PetscLogEventRegister("Sort", 0, &event)); 46 PetscCall(PetscLogEventBegin(event, 0, 0, 0, 0)); 47 48 PetscCall(PetscRandomSeed(rnd)); 49 for (i = 0; i < n; i++) { 50 PetscCall(PetscRandomGetValue(rnd, &value)); 51 values[i] = (PetscInt)(n * PetscRealPart(value) + 2.0); 52 /* printf("value[%d] = %g\n",i,value); */ 53 } 54 PetscCall(PetscSortInt(n, values)); 55 PetscCall(PetscLogEventEnd(event, 0, 0, 0, 0)); 56 57 for (i = 1; i < n; i++) PetscCheck(values[i] >= values[i - 1], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Values not sorted"); 58 PetscCall(PetscFree(values)); 59 PetscCall(PetscRandomDestroy(&rnd)); 60 61 PetscCall(PetscFinalize()); 62 return 0; 63 } 64 65 /*TEST 66 67 test: 68 69 test: 70 suffix: 2 71 nsize: 2 72 output_file: output/ex1_1.out 73 74 test: 75 suffix: 3 76 args: -view_randomvalues 0 77 78 TEST*/ 79