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/* tsqr -- test file for mpc_sqr.
Copyright (C) 2005 Andreas Enge
This file is part of the MPC Library.
The MPC 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 MPC 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 MPC Library; see the file COPYING.LIB. If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */
#include <stdio.h>
#include <stdlib.h>
#include "gmp.h"
#include "mpfr.h"
#include "mpc.h"
#include "mpc-impl.h"
#define SIGN(x) (((x) == 0 ? 0 : ((x) > 0 ? 1 : -1)))
void cmpabs (mpc_srcptr, mpfr_rnd_t);
void testabs (mpc_ptr);
void cmpabs (mpc_srcptr x, mpfr_rnd_t rnd)
/* computes the absolute value of x with the two functions defined in */
/* abs.c with rounding mode rnd and compares the results and return */
/* values. We only consider cases where all precisions are identical. */
/* We also compute the result with four times the precision and check */
/* whether the rounding is correct. Error reports in this part of the */
/* algorithm might still be wrong, though, since there are two */
/* consecutive roundings. */
{
mpfr_t res1, res2, res3;
int inexact1, inexact2;
mpfr_init2 (res1, MPC_MAX_PREC (x));
mpfr_init2 (res2, MPC_MAX_PREC (x));
mpfr_init2 (res3, 4 * MPC_MAX_PREC (x));
inexact1 = mpc_abs (res1, x, rnd);
inexact2 = mpc_abs_basic (res2, x, rnd);
if (mpfr_cmp (res1, res2))
{
fprintf (stderr, "abs and abs_basic differ for rnd=%s \nx=",
mpfr_print_rnd_mode(rnd));
mpc_out_str (stderr, 2, 0, x, MPC_RNDNN);
fprintf (stderr, "\nabs gives ");
mpfr_out_str (stderr, 2, 0, res1, GMP_RNDN);
fprintf (stderr, "\nabs_basic gives ");
mpfr_out_str (stderr, 2, 0, res2, GMP_RNDN);
fprintf (stderr, "\n");
exit (1);
}
if (SIGN (inexact1) != SIGN (inexact2))
{
fprintf (stderr, "The return values of abs and abs_basic differ for rnd=%s \nx= ",
mpfr_print_rnd_mode(rnd));
mpc_out_str (stderr, 2, 0, x, MPC_RNDNN);
fprintf (stderr, "\n|x| = ");
mpfr_out_str (stderr, 2, 0, res1, GMP_RNDN);
fprintf (stderr, "\nabs gives %i", inexact1);
fprintf (stderr, "\nabs_basic gives %i", inexact2);
fprintf (stderr, "\n");
exit (1);
}
if ( (rnd == GMP_RNDU && (inexact1 < 0 || inexact2 < 0))
|| ((rnd == GMP_RNDD || rnd == GMP_RNDZ)
&& (inexact1 > 0 || inexact2 > 0)))
{
fprintf (stderr, "Incorrect return value in abs or abs_basic for rnd=%s \nx= ",
mpfr_print_rnd_mode(rnd));
mpc_out_str (stderr, 2, 0, x, MPC_RNDNN);
fprintf (stderr, "\n|x| = ");
mpfr_out_str (stderr, 2, 0, res1, GMP_RNDN);
fprintf (stderr, "\nabs gives %i", inexact1);
fprintf (stderr, "\nabs_basic gives %i", inexact2);
fprintf (stderr, "\n");
exit (1);
}
mpc_abs (res3, x, rnd);
mpfr_set (res2, res3, rnd);
if (mpfr_cmp (res1, res2))
{
fprintf (stderr, "rounding in abs might be incorrect for rnd=%s \nx=",
mpfr_print_rnd_mode(rnd));
mpc_out_str (stderr, 2, 0, x, MPC_RNDNN);
fprintf (stderr, "\nabs gives ");
mpfr_out_str (stderr, 2, 0, res1, GMP_RNDN);
fprintf (stderr, "\nabs quadruple precision gives ");
mpfr_out_str (stderr, 2, 0, res3, GMP_RNDN);
fprintf (stderr, "\nand is rounded to ");
mpfr_out_str (stderr, 2, 0, res2, GMP_RNDN);
fprintf (stderr, "\n");
exit (1);
}
mpfr_clear (res1);
mpfr_clear (res2);
mpfr_clear (res3);
}
void testabs (mpc_ptr x)
/* executes the test for all rounding modes and all possible signs for */
/* the real and the imaginary part */
{
mpfr_rnd_t rnd;
int i, j;
for (i = 0; i < 2; i++)
{
mpfr_neg (MPC_RE (x), MPC_RE (x), GMP_RNDN);
for (j = 0; j < 2; j++)
{
mpfr_neg (MPC_IM (x), MPC_IM (x), GMP_RNDN);
for (rnd = 0; rnd < 4; rnd++)
cmpabs (x, rnd);
}
}
}
int main()
{
mpc_t x;
mpfr_t eps;
mp_prec_t prec;
mpc_init2 (x, 1000);
mpfr_init2 (eps, 10);
/* The most interesting cases arise when real and imaginary part differ */
/* much, since only then abs and abs_basic actually differ. */
/* Check 1, 1+epsilon, (1+epsilon) + epsilon*i and the same values with */
/* real and imaginary part swapped for epsilon small powers of 2. */
mpfr_set_ui (eps, 1, GMP_RNDN);
mpfr_div_2ui (eps, eps, 200, GMP_RNDN);
for (prec = 2; prec < 1000; prec += 222)
{
mpc_set_prec (x, prec);
mpc_set_ui_ui (x, 1, 0, MPC_RNDNN);
testabs (x);
mpfr_set (MPC_IM (x), eps, GMP_RNDN);
testabs (x);
mpfr_add_ui (MPC_RE (x), eps, 1, GMP_RNDN);
testabs (x);
mpc_set_ui_ui (x, 0, 1, MPC_RNDNN);
testabs (x);
mpfr_set (MPC_RE (x), eps, GMP_RNDN);
testabs (x);
mpfr_add_ui (MPC_IM (x), eps, 1, GMP_RNDN);
testabs (x);
}
mpc_clear (x);
return 0;
}
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