pi2.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <gmp.h>
   4 #include "cf.h"
   5
   6 // Converges extremely slowly. Not worth converting to decimal or
   7 // continued fraction form.
   8 static void *pi_six_sequence(cf_t cf) {
   9   mpz_t num, denom, t;
  10   mpz_init(num);
  11   mpz_init(denom);
  12   mpz_init(t);
  13
  14   mpz_set_ui(denom, 3);
  15   cf_put(cf, denom);
  16
  17   mpz_set_ui(num, 1);
  18   cf_put(cf, num);
  19   mpz_set_ui(t, 8);
  20
  21   mpz_set_ui(denom, 6);
  22   while(cf_wait(cf)) {
  23     cf_put(cf, denom);
  24     mpz_add(num, num, t);
  25     cf_put(cf, num);
  26     mpz_add_ui(t, t, 8);
  27   }
  28
  29   mpz_clear(num);
  30   mpz_clear(denom);
  31   mpz_clear(t);
  32   return NULL;
  33 }
  34
  35 int main() {
  36   mpz_t z;
  37   mpz_t a, b, c, d;
  38   mpz_init(z);
  39   cf_t pi, conv;
  40   pi = cf_new(pi_six_sequence, NULL);
  41   mpz_init(a); mpz_init(b); mpz_init(c); mpz_init(d);
  42   mpz_set_ui(a, 1); mpz_set_ui(b, 0);
  43   mpz_set_ui(c, 0); mpz_set_ui(d, 1);
  44
  45   conv = cf_new_nonregular_mobius_to_decimal(pi, a, b, c, d);
  46   for (int i = 1; i <= 5000; i++) {
  47     cf_get(z, conv);
  48     gmp_printf("%Zd\n",z);
  49   }
  50   printf("\n");
  51   cf_free(conv);
  52   cf_free(pi);
  53   mpz_clear(z);
  54   mpz_clear(d); mpz_clear(c); mpz_clear(b); mpz_clear(a);
  55   return 0;
  56 }