/* Test mpf_sqrt, mpf_mul.

Copyright 1996, 2001, 2004 Free Software Foundation, Inc.

This file is part of the GNU MP Library test suite.

The GNU MP Library test suite is free software; you can redistribute it

and/or modify it under the terms of the GNU 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 MP Library test suite 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 General

Public License for more details.

You should have received a copy of the GNU General Public License along with

the GNU MP Library test suite.  If not, see https://www.gnu.org/licenses/.  */

#include <stdio.h>

#include <stdlib.h>

#include "gmp.h"

#include "gmp-impl.h"

#include "tests.h"

#ifndef SIZE

#define SIZE 16

#endif

void

check_rand1 (int argc, char **argv)

{

  mp_size_t size;

  mp_exp_t exp;

  int reps = 20000;

  int i;

  mpf_t x, y, y2;

  mp_size_t bprec = 100;

  mpf_t rerr, max_rerr, limit_rerr;

  if (argc > 1)

    {

      reps = strtol (argv[1], 0, 0);

      if (argc > 2)

	bprec = strtol (argv[2], 0, 0);

    }

  mpf_set_default_prec (bprec);

  mpf_init_set_ui (limit_rerr, 1);

  mpf_div_2exp (limit_rerr, limit_rerr, bprec);

#if VERBOSE

  mpf_dump (limit_rerr);

#endif

  mpf_init (rerr);

  mpf_init_set_ui (max_rerr, 0);

  mpf_init (x);

  mpf_init (y);

  mpf_init (y2);

  for (i = 0; i < reps; i++)

    {

      size = urandom () % SIZE;

      exp = urandom () % SIZE;

      mpf_random2 (x, size, exp);

      mpf_sqrt (y, x);

      MPF_CHECK_FORMAT (y);

      mpf_mul (y2, y, y);

      mpf_reldiff (rerr, x, y2);

      if (mpf_cmp (rerr, max_rerr) > 0)

	{

	  mpf_set (max_rerr, rerr);

#if VERBOSE

	  mpf_dump (max_rerr);

#endif

	  if (mpf_cmp (rerr, limit_rerr) > 0)

	    {

	      printf ("ERROR after %d tests\n", i);

	      printf ("   x = "); mpf_dump (x);

	      printf ("   y = "); mpf_dump (y);

	      printf ("  y2 = "); mpf_dump (y2);

	      printf ("   rerr       = "); mpf_dump (rerr);

	      printf ("   limit_rerr = "); mpf_dump (limit_rerr);

              printf ("in hex:\n");

              mp_trace_base = 16;

	      mpf_trace ("   x  ", x);

	      mpf_trace ("   y  ", y);

	      mpf_trace ("   y2 ", y2);

	      mpf_trace ("   rerr      ", rerr);

	      mpf_trace ("   limit_rerr", limit_rerr);

	      abort ();

	    }

	}

    }

  mpf_clear (limit_rerr);

  mpf_clear (rerr);

  mpf_clear (max_rerr);

  mpf_clear (x);

  mpf_clear (y);

  mpf_clear (y2);

}

void

check_rand2 (void)

{

  unsigned long      max_prec = 20;

  unsigned long      min_prec = __GMPF_BITS_TO_PREC (1);

  gmp_randstate_ptr  rands = RANDS;

  unsigned long      x_prec, r_prec;

  mpf_t              x, r, s;

  int                i;

  mpf_init (x);

  mpf_init (r);

  mpf_init (s);

  refmpf_set_prec_limbs (s, 2*max_prec+10);

  for (i = 0; i < 500; i++)

    {

      /* input precision */

      x_prec = gmp_urandomm_ui (rands, max_prec-min_prec) + min_prec;

      refmpf_set_prec_limbs (x, x_prec);

      /* result precision */

      r_prec = gmp_urandomm_ui (rands, max_prec-min_prec) + min_prec;

      refmpf_set_prec_limbs (r, r_prec);

      mpf_random2 (x, x_prec, 1000);

      mpf_sqrt (r, x);

      MPF_CHECK_FORMAT (r);

      /* Expect to prec limbs of result.

         In the current implementation there's no stripping of low zero

         limbs in mpf_sqrt, so size should be exactly prec.  */

      if (SIZ(r) != r_prec)

        {

          printf ("mpf_sqrt wrong number of result limbs\n");

          mpf_trace ("  x", x);

          mpf_trace ("  r", r);

          printf    ("  r_prec=%lu\n", r_prec);

          printf    ("  SIZ(r)  %ld\n", (long) SIZ(r));

          printf    ("  PREC(r) %ld\n", (long) PREC(r));

          abort ();

        }

      /* Must have r^2 <= x, since r has been truncated. */

      mpf_mul (s, r, r);

      if (! (mpf_cmp (s, x) <= 0))

        {

          printf    ("mpf_sqrt result too big\n");

          mpf_trace ("  x", x);

          printf    ("  r_prec=%lu\n", r_prec);

          mpf_trace ("  r", r);

          mpf_trace ("  s", s);

          abort ();

        }

      /* Must have (r+ulp)^2 > x, or else r is too small. */

      refmpf_add_ulp (r);

      mpf_mul (s, r, r);

      if (! (mpf_cmp (s, x) > 0))

        {

          printf    ("mpf_sqrt result too small\n");

          mpf_trace ("  x", x);

          printf    ("  r_prec=%lu\n", r_prec);

          mpf_trace ("  r+ulp", r);

          mpf_trace ("  s", s);

          abort ();

        }

    }

  mpf_clear (x);

  mpf_clear (r);

  mpf_clear (s);

}

int

main (int argc, char **argv)

{

  tests_start ();

  mp_trace_base = -16;

  check_rand1 (argc, argv);

  check_rand2 ();

  tests_end ();

  exit (0);

}