/* Test file for mpfr_agm.

Copyright 1999, 2001, 2002, 2003, 2004, 2005 Free Software Foundation, Inc.

This file is part of the MPFR Library.

The 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 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 MPFR Library; see the file COPYING.LIB.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Place, Fifth Floor, Boston,
MA 02110-1301, USA. */

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

#include "mpfr-test.h"

#define check(a,b,r) check4(a,b,r,0.0)

static void
check4 (const char *as, const char *bs, mp_rnd_t rnd_mode, const char *res)
{
  mpfr_t ta, tb, tres;

  mpfr_inits2(53, ta, tb, tres, NULL);

  mpfr_set_str1 (ta, as);
  mpfr_set_str1 (tb, bs);

  mpfr_agm(tres, ta, tb, rnd_mode);

  if (mpfr_cmp_str1 (tres, res))
    {
      printf ("mpfr_agm failed for a=%s, b=%s, rnd_mode=%d\n",as,bs,rnd_mode);
      printf ("expected result is %s, got ",res);
      mpfr_out_str(stdout, 10, 0, tres, GMP_RNDN);
      putchar('\n');
      exit (1);
  }
  mpfr_clears (ta, tb, tres, NULL);
}

static void
check_large (void)
{
  mpfr_t a, b, agm;
  int inex;

  mpfr_init2 (a, 82);
  mpfr_init2 (b, 82);
  mpfr_init2 (agm, 82);

  mpfr_set_ui (a, 1, GMP_RNDN);
  mpfr_set_str_binary (b, "0.1111101100001000000001011000110111101000001011111000100001000101010100011111110010E-39");
  mpfr_agm (agm, a, b, GMP_RNDN);
  mpfr_set_str_binary (a, "0.1110001000111101101010101010101101001010001001001011100101111011110101111001111100E-4");
  if (mpfr_cmp (agm, a))
    {
      printf ("mpfr_agm failed for precision 82\n");
      exit (1);
    }

  /* problem found by Damien Fischer <damien@maths.usyd.edu.au> 4 Aug 2003:
     produced a division by zero exception */
  mpfr_set_prec (a, 268);
  mpfr_set_prec (b, 268);
  mpfr_set_prec (agm, 268);
  mpfr_set_str (a, "703.93543315330225238487276503953366664991725089988315253092140138947103394917006", 10, GMP_RNDN);
  mpfr_set_str (b, "703.93543315330225238487279020523738740563816490895994499256063816906728642622316", 10, GMP_RNDN);
  mpfr_agm (agm, a, b, GMP_RNDN);

  mpfr_set_prec (a, 18);
  mpfr_set_prec (b, 70);
  mpfr_set_prec (agm, 67);
  mpfr_set_str_binary (a, "0.111001111100101000e8");
  mpfr_set_str_binary (b, "0.1101110111100100010100110000010111011011011100110100111001010100100001e10");
  inex = mpfr_agm (agm, a, b, GMP_RNDN);
  mpfr_set_str_binary (b, "0.1111110010011101101100010101011011010010010000001010100011000110011e9");
  if (mpfr_cmp (agm, b))
    {
      printf ("Error in mpfr_agm (1)\n");
      exit (1);
    }
  if (inex >= 0)
    {
      printf ("Wrong flag for mpfr_agm (1)\n");
      exit (1);
    }

  /* test worst case: 9 consecutive ones after the last bit */
  mpfr_set_prec (a, 2);
  mpfr_set_prec (b, 2);
  mpfr_set_ui (a, 1, GMP_RNDN);
  mpfr_set_ui (b, 2, GMP_RNDN);
  mpfr_set_prec (agm, 904);
  mpfr_agm (agm, a, b, GMP_RNDZ);

  mpfr_clear (a);
  mpfr_clear (b);
  mpfr_clear (agm);
}

static void
check_nans (void)
{
  mpfr_t  x, y, m;

  mpfr_init2 (x, 123L);
  mpfr_init2 (y, 123L);
  mpfr_init2 (m, 123L);

  /* agm(1,nan) == nan */
  mpfr_set_ui (x, 1L, GMP_RNDN);
  mpfr_set_nan (y);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_nan_p (m));

  /* agm(1,+inf) == +inf */
  mpfr_set_ui (x, 1L, GMP_RNDN);
  mpfr_set_inf (y, 1);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_inf_p (m));
  MPFR_ASSERTN (mpfr_sgn (m) > 0);

  /* agm(+inf,+inf) == +inf */
  mpfr_set_inf (x, 1);
  mpfr_set_inf (y, 1);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_inf_p (m));
  MPFR_ASSERTN (mpfr_sgn (m) > 0);

  /* agm(-inf,+inf) == nan */
  mpfr_set_inf (x, -1);
  mpfr_set_inf (y, 1);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_nan_p (m));

  /* agm(+0,+inf) == nan */
  mpfr_set_ui (x, 0, GMP_RNDN);
  mpfr_set_inf (y, 1);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_nan_p (m));

  /* agm(+0,1) == +0 */
  mpfr_set_ui (x, 0, GMP_RNDN);
  mpfr_set_ui (y, 1, GMP_RNDN);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (MPFR_IS_ZERO (m) && MPFR_IS_POS(m));

  /* agm(-0,1) == +0 */
  mpfr_set_ui (x, 0, GMP_RNDN);
  mpfr_neg (x, x, GMP_RNDN);
  mpfr_set_ui (y, 1, GMP_RNDN);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (MPFR_IS_ZERO (m) && MPFR_IS_POS(m));

  /* agm(-0,+0) == +0 */
  mpfr_set_ui (x, 0, GMP_RNDN);
  mpfr_neg (x, x, GMP_RNDN);
  mpfr_set_ui (y, 0, GMP_RNDN);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (MPFR_IS_ZERO (m) && MPFR_IS_POS(m));

  /* agm(1,1) == 1 */
  mpfr_set_ui (x, 1, GMP_RNDN);
  mpfr_set_ui (y, 1, GMP_RNDN);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_cmp_ui (m ,1) == 0);

  /* agm(-1,-2) == NaN */
  mpfr_set_si (x, -1, GMP_RNDN);
  mpfr_set_si (y, -2, GMP_RNDN);
  mpfr_agm (m, x, y, GMP_RNDN);
  MPFR_ASSERTN (mpfr_nan_p (m));

  mpfr_clear (x);
  mpfr_clear (y);
  mpfr_clear (m);
}

#define TEST_FUNCTION mpfr_agm
#define TWO_ARGS
#include "tgeneric.c"

int
main (int argc, char* argv[])
{
  MPFR_TEST_USE_RANDS ();
  tests_start_mpfr ();

  check_nans ();

  check_large ();
  check4 ("2.0", "1.0", GMP_RNDN, "1.45679103104690677029");
  check4 ("6.0", "4.0", GMP_RNDN, "4.94936087247260925182");
  check4 ("62.0", "61.0", GMP_RNDN, "6.14989837188450749750e+01");
  check4 ("0.5", "1.0", GMP_RNDN, "7.28395515523453385143e-01");
  check4 ("1.0", "2.0", GMP_RNDN, "1.45679103104690677029");
  check4 ("234375765.0", "234375000.0", GMP_RNDN, "2.3437538249984395504e8");
  check4 ("8.0", "1.0", GMP_RNDU, "3.615756177597362786");
  check4 ("1.0", "44.0", GMP_RNDU, "1.33658354512981247808e1");
  check4 ("1.0", "3.7252902984619140625e-9", GMP_RNDU,
          "7.55393356971199025907e-02");
  test_generic (2, 300, 17);

  tests_end_mpfr ();
  return 0;
}