int main(int argc, char *argv[]) {
int n, i, diag_size, mid_size, short_size, execs = 0;
int *diag, *l_upper, *l_lower, *u_upper, *u_lower;
double *x, *newx, *b, *true_x;
double residual = 10000;
struct timeb start, stop;
int time_diff;
if (argc != 2) {
printf("Format: jacobi <n>\n");
return 1;
}
n = atoi(argv[1]);
//start timing here
ftime(&start);
gen_laplace_mat(n, &diag, &l_upper, &l_lower, &u_upper, &u_lower);
diag_size = n * n;
mid_size = n * n - 1;
short_size = n * n - n;
x = malloc(diag_size * sizeof(double));
newx = malloc(diag_size * sizeof(double));
true_x = malloc(diag_size * sizeof(double));
b = malloc(diag_size * sizeof(double));
init_x(diag_size, x);
init_true_x(diag_size, true_x);
init_b(n, diag_size, mid_size, short_size, diag, l_upper, l_lower, u_upper, u_lower, true_x, b);
while (residual > 0.001 && execs < 100000) {
calc_newx(n, diag_size, mid_size, short_size, diag, l_upper, l_lower, u_upper, u_lower, x, b, newx);
for (i = 0; i < diag_size; i++) {
x[i] = newx[i];
}
residual = calc_resid(n, diag_size, mid_size, short_size, diag, l_upper, l_lower, u_upper, u_lower, x, b);
execs++;
}
// end timing here
ftime(&stop);
time_diff = (int)(1000.0 * (stop.time - start.time) + (stop.millitm - start.millitm));
printf("Finished in %u milliseconds.\n", time_diff);
printf("In %d iterations, got residual of %f\n", execs, residual);
return 0;
}
int main(int argc, char *argv[])
{
if (argc < 3){
printf("Arguments required, Quitting...\n");
return 1;
}
int N = atoi(argv[1]);
int max_iter = atoi(argv[2]);
double h2 = 1.0/(N+1)/(N+1);
double *u, *uc, *f;
// allocate arrays
int n_per_proc = N + 2;
u = (double *) malloc(n_per_proc*sizeof (double));
uc = (double *) malloc(n_per_proc*sizeof (double));
f = (double *) malloc(n_per_proc*sizeof (double));
// initialize f and u
int i;
for (i = 0; i < n_per_proc-1; i++) {
f[i] = 1.0;
u[i] = 0.0;
}
// Begin iterations
double resid_init, resid_cur;
resid_init = calc_resid(n_per_proc, h2, f, u);
resid_cur = resid_init;
printf("%f\n", resid_init);
int iter = 0;
timestamp_type t1, t2;
get_timestamp(&t1);
while (resid_cur / resid_init > STOP_ITER_RAT){
/* resid_cur = 0.0; */
u[0] = 0.0;
u[n_per_proc - 1] = 0.0;
jacobi_laplace(n_per_proc, h2, f, u, uc);
resid_cur = calc_resid(n_per_proc, h2, f, u);
printf("Resid is %f\n", resid_cur );
if (++iter > max_iter) break;
}
get_timestamp(&t2);
printf("Total time: %f\n", timestamp_diff_in_seconds(t1,t2));
// deallocate
free(f);
free(u);
free(uc);
return 0;
}
