int main(void)
{
double abs_error;
int n = 100000;
double pi;
printf("Leibniz series \n");
do{
pi = pi_leibniz(n);
abs_error = fabs(pi - M_PI);
printf("%8d %20.15f %20.15f\n", n, pi, abs_error);
n += 100000;
}while(abs_error > .000001);
printf("BBP\n");
n = 1;
do{
pi = pi_bbp(n);
abs_error = fabs(pi - M_PI);
printf("%8d %20.15f %20.15f\n", n, pi, abs_error);
n += 1;
}while(abs_error > .000001);
printf("\n");
clock_t start, stop;
int n_one = 1000000;
int n_two = 4;
int leib_runs = 100;
start = clock();
for(int i = 0; i < leib_runs; i++){
pi = pi_leibniz(n_one);
}
stop = clock();
double t1 = 1000*((double)(stop-start))/(CLOCKS_PER_SEC*leib_runs);
printf("t1 %.6f \n", t1);
int bbp_runs = 2000000;
start = clock();
for(int i = 0; i < bbp_runs; i++){
pi = pi_bbp(n_two);
}
stop = clock();
double t2 = 1000*((double)(stop-start))/(1.0*CLOCKS_PER_SEC*bbp_runs);
printf("t2 %.6f \n", t2);
printf("%21.0f \n", t1/t2);
return 0;
}
int main(void)
{
int i;
double pi = 0;
for (i =100000; i < 2000000; i += 100000)
{
if (fabs(pi - M_PI) < pow(10, -6))
{
return 0;
}
else
{
pi = pi_leibniz(i);
printf("%8d %20.15f %20.15f\n", i, pi, fabs(pi - M_PI));
}
}
}
int main(void) { // j and n are just used as iteration variables n
int i = 1;
double pi;
double abserr;
double tol = pow ( 10 , -6 );
do { //doubles the amount of terms in the pi_leibniz series until error is less than 10^-6
pi = pi_leibniz (i);
abserr = fabs (pi - M_PI);
printf ("%8d %20.15f %20.15f\n", i, pi, abserr);
i *= 2;
} while ( abserr > tol );
i = 1;
do { //doubles the amount of terms in the pi_bbp series until error is less than 10^-6
pi = pi_bbp (i);
abserr = fabs (pi - M_PI);
printf ("%8d %20.15f %20.15f\n", i, pi, abserr);
i *= 2;
} while ( abserr > tol );
// end of code figuring out number of terms needed for 10^-6 accuracy
int count = 10;
double time;
double time1;
double tmin = 1;
double tmax = 2;
printf("pi_leibniz\n");
do {
timer_start ();
for (int k = 0; k <= count; k++) {
pi_leibniz (1048576);
}
time = timer_stop ();
time1 = time / count;
printf (" %10.2f usec %10.6f sec %10d\n",
time1 * 1.e6, time, count);
/*
* adjust count such that cpu time is between
* tmin and tmax
*/
count = adjust_rep_count (count, time, tmin, tmax);
} while ((time > tmax) || (time < tmin));
printf("pi_pbb\n");
do {
timer_start ();
for (int k = 0; k < count; k++) {
pi_bbp (4);
}
time = timer_stop ();
time1 = time / count;
printf (" %10.2f usec %10.6f sec %10d\n", time1 * 1.e6, time, count);
/*
* adjust count such that cpu time is between
* tmin and tmax
*/
count = adjust_rep_count (count, time, tmin, tmax);
} while ((time > tmax) || (time < tmin));
return 0;
}
