Actual source code: ex1.c
2: static char help[] = "Tests PetscRandom functions.\n\n";
4: #include <petscsys.h>
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: */
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: #if defined(PETSC_USE_LOG)
20: PetscLogEvent event;
21: #endif
24: PetscInitialize(&argc, &argv, (char *)0, help);
25: MPI_Comm_rank(PETSC_COMM_WORLD, &rank);
26: PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL);
27: PetscOptionsGetInt(NULL, NULL, "-view_randomvalues", &view_rank, NULL);
29: PetscRandomCreate(PETSC_COMM_WORLD, &rnd);
30: /* force imaginary part of random number to always be zero; thus obtain reproducible results with real and complex numbers */
31: PetscRandomSetInterval(rnd, 0.0, 1.0);
32: PetscRandomSetFromOptions(rnd);
34: PetscMalloc1(n, &values);
35: for (i = 0; i < n; i++) {
36: PetscRandomGetValue(rnd, &value);
37: avg += value;
38: if (view_rank == (PetscInt)rank) PetscPrintf(PETSC_COMM_SELF, "[%d] value[%" PetscInt_FMT "] = %6.4e\n", rank, i, (double)PetscRealPart(value));
39: values[i] = (PetscInt)(n * PetscRealPart(value) + 2.0);
40: }
41: avg = avg / ((PetscReal)n);
42: if (view_rank == (PetscInt)rank) PetscPrintf(PETSC_COMM_SELF, "[%d] Average value %6.4e\n", rank, (double)PetscRealPart(avg));
44: PetscSortInt(n, values);
46: PetscLogEventRegister("Sort", 0, &event);
47: PetscLogEventBegin(event, 0, 0, 0, 0);
49: PetscRandomSeed(rnd);
50: for (i = 0; i < n; i++) {
51: PetscRandomGetValue(rnd, &value);
52: values[i] = (PetscInt)(n * PetscRealPart(value) + 2.0);
53: /* printf("value[%d] = %g\n",i,value); */
54: }
55: PetscSortInt(n, values);
56: PetscLogEventEnd(event, 0, 0, 0, 0);
59: PetscFree(values);
60: PetscRandomDestroy(&rnd);
62: PetscFinalize();
63: return 0;
64: }
66: /*TEST
68: test:
70: test:
71: suffix: 2
72: nsize: 2
73: output_file: output/ex1_1.out
75: test:
76: suffix: 3
77: args: -view_randomvalues 0
79: TEST*/