/* Test file for mpfr_const_pi.

Copyright 1999, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
Contributed by the Arenaire and Cacao projects, INRIA.

This file is part of the GNU MPFR Library.

The GNU MPFR Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or (at your
option) any later version.

The GNU MPFR Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser General Public License
along with the GNU MPFR Library; see the file COPYING.LIB.  If not, write to
the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
MA 02110-1301, USA. */

#include <stdio.h>
#include <stdlib.h>

#include "mpfr-test.h"

/* tconst_pi [prec] [rnd] [0 = no print] */

static void
check_large (void)
{
  mpfr_t x, y, z;

  mpfr_init2 (x, 20000);
  mpfr_init2 (y, 21000);
  mpfr_init2 (z, 11791);

  /* The algo failed to round for p=11791. */
  (mpfr_const_pi) (z, GMP_RNDU);
  mpfr_const_pi (x, GMP_RNDN); /* First one ! */
  mpfr_const_pi (y, GMP_RNDN); /* Then the other - cache - */
  mpfr_prec_round (y, 20000, GMP_RNDN);
  if (mpfr_cmp (x, y)) {
    printf ("const_pi: error for large prec (%d)\n", 1);
    exit (1);
  }
  mpfr_prec_round (y, 11791, GMP_RNDU);
  if (mpfr_cmp (z, y)) {
    printf ("const_pi: error for large prec (%d)\n", 2);
    exit (1);
  }

  /* a worst-case to exercise recomputation */
  if (MPFR_PREC_MAX > 33440) {
    mpfr_set_prec (x, 33440);
    mpfr_const_pi (x, GMP_RNDZ);
  }

  mpfr_clears (x, y, z, (mpfr_ptr) 0);
}

/* Wrapper for tgeneric */
static int
my_const_pi (mpfr_ptr x, mpfr_srcptr y, mp_rnd_t r)
{
  return mpfr_const_pi (x, r);
}

#define RAND_FUNCTION(x) mpfr_set_ui ((x), 0, GMP_RNDN)
#define TEST_FUNCTION my_const_pi
#include "tgeneric.c"

static void
bug20091030 (void)
{
  mpfr_t x, x_ref;
  int inex, inex_ref;
  mp_prec_t p;
  int r;

  mpfr_free_cache ();
  mpfr_init2 (x, MPFR_PREC_MIN);
  for (p = MPFR_PREC_MIN; p <= 100; p++)
    {
      mpfr_set_prec (x, p);
      inex = mpfr_const_pi (x, GMP_RNDU);
      if (inex < 0)
        {
          printf ("Error, inex < 0 for RNDU (prec=%lu)\n", p);
          exit (1);
        }
      inex = mpfr_const_pi (x, GMP_RNDD);
      if (inex > 0)
        {
          printf ("Error, inex > 0 for RNDD (prec=%lu)\n", p);
          exit (1);
        }
    }
  mpfr_free_cache ();
  mpfr_init2 (x_ref, MPFR_PREC_MIN);
  for (p = MPFR_PREC_MIN; p <= 100; p++)
    {
      mpfr_set_prec (x, p + 10);
      mpfr_const_pi (x, GMP_RNDN);
      mpfr_set_prec (x, p);
      mpfr_set_prec (x_ref, p);
      for (r = 0; r < GMP_RND_MAX; r++)
        {
          inex = mpfr_const_pi (x, (mpfr_rnd_t) r);
          inex_ref = mpfr_const_pi_internal (x_ref, (mpfr_rnd_t) r);
          if (inex != inex_ref || mpfr_cmp (x, x_ref) != 0)
            {
              printf ("mpfr_const_pi and mpfr_const_pi_internal disagree\n");
              printf ("mpfr_const_pi gives ");
              mpfr_dump (x);
              printf ("mpfr_const_pi_internal gives ");
              mpfr_dump (x_ref);
              printf ("inex=%d inex_ref=%d\n", inex, inex_ref);
              exit (1);
            }
        }
    }
  mpfr_clear (x);
  mpfr_clear (x_ref);
}

int
main (int argc, char *argv[])
{
  mpfr_t x;
  mp_prec_t p;
  mp_rnd_t rnd;

  tests_start_mpfr ();

  p = 53;
  if (argc > 1)
    {
      long a = atol (argv[1]);
      if (a >= MPFR_PREC_MIN && a <= MPFR_PREC_MAX)
        p = a;
    }

  rnd = (argc > 2) ? (mp_rnd_t) atoi(argv[2]) : GMP_RNDZ;

  mpfr_init2 (x, p);
  mpfr_const_pi (x, rnd);
  if (argc >= 2)
    {
      if (argc < 4 || atoi (argv[3]) != 0)
        {
          printf ("Pi=");
          mpfr_out_str (stdout, 10, 0, x, rnd);
          puts ("");
        }
    }
  else if (mpfr_cmp_str1 (x, "3.141592653589793116") )
    {
      printf ("mpfr_const_pi failed for prec=53\n");
      mpfr_out_str (stdout, 10, 0, x, GMP_RNDN); putchar('\n');
      exit (1);
    }

  mpfr_set_prec (x, 32);
  mpfr_const_pi (x, GMP_RNDN);
  if (mpfr_cmp_str1 (x, "3.141592653468251") )
    {
      printf ("mpfr_const_pi failed for prec=32\n");
      exit (1);
    }

  mpfr_clear (x);

  bug20091030 ();

  check_large ();

  test_generic (2, 200, 1);

  tests_end_mpfr ();

  return 0;
}
