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
23: PetscFunctionBeginUser;
24: PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
25: PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
26: PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
27: PetscCall(PetscOptionsGetInt(NULL, NULL, "-view_randomvalues", &view_rank, NULL));
29: PetscCall(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: PetscCall(PetscRandomSetInterval(rnd, 0.0, 1.0));
32: PetscCall(PetscRandomSetFromOptions(rnd));
34: PetscCall(PetscMalloc1(n, &values));
35: for (i = 0; i < n; i++) {
36: PetscCall(PetscRandomGetValue(rnd, &value));
37: avg += value;
38: if (view_rank == (PetscInt)rank) PetscCall(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) PetscCall(PetscPrintf(PETSC_COMM_SELF, "[%d] Average value %6.4e\n", rank, (double)PetscRealPart(avg)));
44: PetscCall(PetscSortInt(n, values));
46: PetscCall(PetscLogEventRegister("Sort", 0, &event));
47: PetscCall(PetscLogEventBegin(event, 0, 0, 0, 0));
49: PetscCall(PetscRandomSeed(rnd));
50: for (i = 0; i < n; i++) {
51: PetscCall(PetscRandomGetValue(rnd, &value));
52: values[i] = (PetscInt)(n * PetscRealPart(value) + 2.0);
53: /* printf("value[%d] = %g\n",i,value); */
54: }
55: PetscCall(PetscSortInt(n, values));
56: PetscCall(PetscLogEventEnd(event, 0, 0, 0, 0));
58: for (i = 1; i < n; i++) PetscCheck(values[i] >= values[i - 1], PETSC_COMM_SELF, PETSC_ERR_PLIB, "Values not sorted");
59: PetscCall(PetscFree(values));
60: PetscCall(PetscRandomDestroy(&rnd));
62: PetscCall(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*/