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