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