dist/tests/tfrac.c

/* Test file for mpfr_frac.

Copyright 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 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 3 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.LESSER.  If not, see
http://www.gnu.org/licenses/ or 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"

#define PIP 70
#define PFP 70
#define PMAX (PIP+2*PFP)

static void
check0 (mpfr_ptr ip, mpfr_ptr fp, mpfr_prec_t prec, mpfr_rnd_t rnd)
{
  mpfr_t sum, tmp, dst, fp2;
  int inex1, inex2;

  mpfr_init2 (sum, PMAX);
  mpfr_init2 (tmp, PMAX);
  mpfr_init2 (dst, prec);
  mpfr_init2 (fp2, prec);

  if (MPFR_SIGN (ip) != MPFR_SIGN (fp))
    {
      printf ("Internal error (1)\n");
      exit (1);
    }
  if (mpfr_add (sum, ip, fp, MPFR_RNDZ))
    {
      printf ("Wrong inexact flag in mpfr_add\n");
      exit (1);
    }
  if (MPFR_SIGN (sum) != MPFR_SIGN (fp))
    {
      printf ("Internal error (2)\n");
      exit (1);
    }

  inex1 = mpfr_frac (dst, sum, rnd);
  inex2 = mpfr_set (fp2, fp, rnd);
  if (inex1 != inex2)
    {
      printf ("Wrong inexact flag in mpfr_frac for\n");
      mpfr_out_str (stdout, 2, 0, sum, MPFR_RNDN);
      printf ("\nGot %d instead of %d\n", inex1, inex2);
      exit (1);
    }
  if (!mpfr_number_p (dst) ||
      MPFR_SIGN (dst) != MPFR_SIGN (fp2) ||
      mpfr_cmp (dst, fp2))
    {
      printf ("Error in mpfr_frac (y, x, %s) with\nx = ",
              mpfr_print_rnd_mode (rnd));
      mpfr_out_str (stdout, 2, 0, sum, MPFR_RNDN);
      printf ("\nGot        ");
      mpfr_out_str (stdout, 2, 0, dst, MPFR_RNDN);
      printf ("\ninstead of ");
      mpfr_out_str (stdout, 2, 0, fp2, MPFR_RNDN);
      printf ("\n");
      exit (1);
    }

  if (prec == PMAX)
    {
      inex1 = mpfr_frac (sum, sum, rnd);
      if (inex1)
        {
          printf ("Wrong inexact flag in mpfr_frac\n");
          exit (1);
        }
      if (!mpfr_number_p (sum) ||
          MPFR_SIGN (sum) != MPFR_SIGN (fp) ||
          mpfr_cmp (sum, fp))
        {
          printf ("Error in mpfr_frac (x, x, %s) with\nx = ",
                  mpfr_print_rnd_mode (rnd));
          mpfr_add (tmp, ip, fp, MPFR_RNDZ);
          mpfr_out_str (stdout, 2, 0, tmp, MPFR_RNDN);
          printf ("\nGot        ");
          mpfr_out_str (stdout, 2, 0, sum, MPFR_RNDN);
          printf ("\ninstead of ");
          mpfr_out_str (stdout, 2, 0, fp, MPFR_RNDN);
          printf ("\n");
          exit (1);
        }
    }

  mpfr_clear (fp2);
  mpfr_clear (dst);
  mpfr_clear (tmp);
  mpfr_clear (sum);
}

static void
check1 (mpfr_ptr ip, mpfr_ptr fp)
{
  int rnd;

  for (rnd = 0; rnd < MPFR_RND_MAX ; rnd++)
    {
      check0 (ip, fp, PMAX, (mpfr_rnd_t) rnd);
      check0 (ip, fp, 70, (mpfr_rnd_t) rnd);
      mpfr_neg (fp, fp, MPFR_RNDN);
      mpfr_neg (ip, ip, MPFR_RNDN);
      check0 (ip, fp, PMAX, (mpfr_rnd_t) rnd);
      check0 (ip, fp, 70, (mpfr_rnd_t) rnd);
      mpfr_neg (fp, fp, MPFR_RNDN);
      mpfr_neg (ip, ip, MPFR_RNDN);
    }
}

static void
special (void)
{
  mpfr_t z, t;

  mpfr_init (z);
  mpfr_init (t);

  mpfr_set_nan (z);
  mpfr_frac (t, z, MPFR_RNDN);
  if (!mpfr_nan_p (t))
    {
      printf ("Error for frac(NaN)\n");
      exit (1);
    }

  mpfr_set_prec (z, 6);
  mpfr_set_prec (t, 3);

  mpfr_set_str_binary (z, "0.101101E3");
  mpfr_frac (t, z, MPFR_RNDN);
  mpfr_set_str_binary (z, "0.101");
  if (mpfr_cmp (t, z))
    {
      printf ("Error in frac(0.101101E3)\n");
      exit (1);
    }

  mpfr_set_prec (z, 34);
  mpfr_set_prec (t, 26);
  mpfr_set_str_binary (z, "0.101101010000010011110011001101E9");
  mpfr_frac (t, z, MPFR_RNDN);
  mpfr_set_str_binary (z, "0.000010011110011001101");
  if (mpfr_cmp (t, z))
    {
      printf ("Error in frac(0.101101010000010011110011001101E9)\n");
      exit (1);
    }

  mpfr_clear (z);
  mpfr_clear (t);
}

static void
bug20090918 (void)
{
  mpfr_t x, y, z;
  mp_limb_t y0;
  int inexy, inexz;
  int r, i;
  char *s[] = { "61680.352935791015625", "61680.999999" };
  mpfr_exp_t emin;

  emin = mpfr_get_emin ();
  mpfr_init2 (x, 32);
  mpfr_init2 (y, 13);

  for (i = 0; i <= 9; i++)
    {
      mpfr_set_str (x, s[i & 1], 10, MPFR_RNDZ);

      RND_LOOP(r)
        {
          set_emin ((i >> 1) - 3);
          inexy = mpfr_frac (y, x, (mpfr_rnd_t) r);
          set_emin (emin);
          y0 = MPFR_MANT(y)[0];
          while (y0 != 0 && (y0 >> 1) << 1 == y0)
            y0 >>= 1;
          if (y0 > 0x2000)
            {
              printf ("Error in bug20090918 (significand has more than"
                      " 13 bits), i = %d, %s.\n", i,
                      mpfr_print_rnd_mode ((mpfr_rnd_t) r));
              exit (1);
            }
          mpfr_init2 (z, 32);
          inexz = mpfr_frac (z, x, MPFR_RNDN);
          MPFR_ASSERTN (inexz == 0);  /* exact */
          inexz = mpfr_prec_round (z, 13, (mpfr_rnd_t) r);
          set_emin ((i >> 1) - 3);
          inexz = mpfr_check_range (z, inexz, (mpfr_rnd_t) r);
          set_emin (emin);
          if (mpfr_cmp0 (y, z) != 0)
            {
              printf ("Error in bug20090918, i = %d, %s.\n", i,
                      mpfr_print_rnd_mode ((mpfr_rnd_t) r));
              printf ("Expected ");
              mpfr_dump (z);
              printf ("Got      ");
              mpfr_dump (y);
              exit (1);
            }
          if (! SAME_SIGN (inexy, inexz))
            {
              printf ("Incorrect ternary value in bug20090918, i = %d, %s.\n",
                      i, mpfr_print_rnd_mode ((mpfr_rnd_t) r));
              printf ("Expected %d, got %d.\n", inexz, inexy);
              exit (1);
            }
          mpfr_clear (z);
        }
    }

  mpfr_clear (x);
  mpfr_clear (y);
}

#define TEST_FUNCTION mpfr_frac
#include "tgeneric.c"

int
main (void)
{
  mpfr_t ip, fp;
  int ni, nf1, nf2;

  tests_start_mpfr ();

  special ();

  mpfr_init2 (ip, PIP);
  mpfr_init2 (fp, PFP);

  for (ni = -1; ni < PIP; ni++)
    {
      if (ni <= 0)
        { /* ni + 1 */
          mpfr_set_si (ip, ni, MPFR_RNDN);
          mpfr_add_ui (ip, ip, 1, MPFR_RNDN);
        }
      else
        { /* 2^ni + 1 */
          mpfr_set_ui (ip, 1, MPFR_RNDN);
          mpfr_mul_2ui (ip, ip, ni, MPFR_RNDN);
          mpfr_add_ui (ip, ip, 1, MPFR_RNDN);
        }

      mpfr_set_ui (fp, 0, MPFR_RNDN);
      check1 (ip, fp);

      for (nf1 = 1; nf1 < PFP; nf1++)
        {
          mpfr_set_ui (fp, 1, MPFR_RNDN);
          mpfr_div_2ui (fp, fp, nf1, MPFR_RNDN);
          check1 (ip, fp);
          nf2 = 1 + (randlimb () % (PFP - 1));
          mpfr_set_ui (fp, 1, MPFR_RNDN);
          mpfr_div_2ui (fp, fp, nf2, MPFR_RNDN);
          mpfr_add_ui (fp, fp, 1, MPFR_RNDN);
          mpfr_div_2ui (fp, fp, nf1, MPFR_RNDN);
          check1 (ip, fp);
        }
    }

  mpfr_set_ui (ip, 1, MPFR_RNDN);
  mpfr_div_ui (ip, ip, 0, MPFR_RNDN);
  mpfr_set_ui (fp, 0, MPFR_RNDN);
  check1 (ip, fp);  /* test infinities */

  mpfr_clear (ip);
  mpfr_clear (fp);

  bug20090918 ();

  test_generic (2, 1000, 10);

  tests_end_mpfr ();
  return 0;
}