int main (int argc, char* argv[]){
    int nodecount, *num_in_links, *num_out_links;

    int err = get_node_stat(&nodecount, &num_in_links, &num_out_links);
    if (err != 0) {
        return err;
    }

    node_t *nodehead;
    err = node_init(&nodehead, num_in_links, num_out_links, 0, nodecount);
    if (err != 0) {
        return err;
    }

    double start, end;

    GET_TIME(start);
    double damp_const = (1.0 - DAMPING_FACTOR) / nodecount;
    double *r = init_result_vector(nodecount, false);
    double *r_pre = init_result_vector(nodecount, true);
    page_rank(r, r_pre, num_out_links, num_in_links, nodecount, nodehead, damp_const);
    free(r_pre);
    GET_TIME(end);

    double delay = end - start;
    Lab4_saveoutput(r, nodecount, delay);

    node_destroy(nodehead, nodecount);
    free(num_in_links);
    free(num_out_links);
    free(r);
}
Ejemplo n.º 2
0
int calculate(double *r, node *A) {
    int i, j;
    double *r_pre;
    double damp_const;
    damp_const = (1.0 - DAMPING_FACTOR) / n;
    int my_rank, comm_sz, local_n;
    double start = 0, end = 0; // for time

    MPI_Init(NULL, NULL);

    /* Get my process rank */
    MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);

    /* Find out how many processes are being used */
    MPI_Comm_size(MPI_COMM_WORLD, &comm_sz);

    r_pre = malloc(n * sizeof(double));

    local_n = n / comm_sz;

    double still_err = 1;
    double *local_r = malloc(local_n * sizeof(double));

    if (my_rank == 0) {
        GET_TIME(start);
    }
    while (still_err > EPSILON) {
        backup_vec(r, r_pre, n);
        for ( i = local_n * my_rank; i < local_n * (my_rank + 1); i++) {
            local_r[i - local_n * my_rank] = 0.0;
            for ( j = 0; j < A[i].size_Di; ++j) {
                local_r[i - local_n * my_rank] += r_pre[A[i].Di[j]] / A[A[i].Di[j]].li;
            }
            local_r[i - local_n * my_rank] *= DAMPING_FACTOR;
            local_r[i - local_n * my_rank] += damp_const;
        }
        MPI_Gather(local_r, local_n, MPI_DOUBLE, r, local_n, MPI_DOUBLE, 0, MPI_COMM_WORLD);
        if (my_rank == 0) {
            still_err = rel_err(r, r_pre, n);
        }
        MPI_Bcast(&still_err, 1, MPI_DOUBLE, 0, MPI_COMM_WORLD);
        MPI_Bcast(r, n, MPI_DOUBLE, 0, MPI_COMM_WORLD);
    }
    if (my_rank == 0) {
        GET_TIME(end);
        printf("%f\n", end-start);
        Lab4_saveoutput(r, n, end-start);
    }

    free(r_pre);

    MPI_Finalize();

    return 0;
}