| version 1.1, 2000/09/09 14:12:19 |
version 1.1.1.2, 2003/08/25 16:06:07 |
|
|
| /* mpfr_set -- copy of a floating-point number |
/* mpfr_set -- copy of a floating-point number |
| |
|
| Copyright (C) 1999 PolKA project, Inria Lorraine and Loria |
Copyright 1999, 2001 Free Software Foundation. |
| |
|
| This file is part of the MPFR Library. |
This file is part of the MPFR Library. |
| |
|
| The MPFR Library is free software; you can redistribute it and/or modify |
The MPFR Library is free software; you can redistribute it and/or modify |
| it under the terms of the GNU Library General Public License as published by |
it under the terms of the GNU Lesser General Public License as published by |
| the Free Software Foundation; either version 2 of the License, or (at your |
the Free Software Foundation; either version 2.1 of the License, or (at your |
| option) any later version. |
option) any later version. |
| |
|
| The MPFR Library is distributed in the hope that it will be useful, but |
The MPFR Library is distributed in the hope that it will be useful, but |
| WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY |
| or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Library General Public |
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public |
| License for more details. |
License for more details. |
| |
|
| You should have received a copy of the GNU Library General Public License |
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 |
along with the MPFR Library; see the file COPYING.LIB. If not, write to |
| the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, |
| MA 02111-1307, USA. */ |
MA 02111-1307, USA. */ |
| |
|
| #include <stdio.h> |
|
| #include "gmp.h" |
#include "gmp.h" |
| #include "gmp-impl.h" |
#include "gmp-impl.h" |
| #include "mpfr.h" |
#include "mpfr.h" |
| |
#include "mpfr-impl.h" |
| |
|
| void |
/* set a to abs(b) * signb: a=b when signb = SIGN(b), a=abs(b) when signb=1 */ |
| #if __STDC__ |
int |
| mpfr_set4(mpfr_ptr a, mpfr_srcptr b, unsigned char rnd_mode, int signb) |
mpfr_set4 (mpfr_ptr a, mpfr_srcptr b, mp_rnd_t rnd_mode, int signb) |
| #else |
|
| mpfr_set4(a, b, rnd_mode, signb) |
|
| mpfr_ptr a; |
|
| mpfr_srcptr b; |
|
| unsigned char rnd_mode; |
|
| int signb; |
|
| #endif |
|
| { |
{ |
| int carry, an, preca = PREC(a), sh; mp_limb_t *ap = MANT(a); |
int inex; |
| |
|
| carry = mpfr_round_raw(ap, MANT(b), PREC(b), (signb<0), preca, rnd_mode); |
if (MPFR_IS_NAN(b)) |
| EXP(a) = EXP(b); |
{ |
| if (carry) { |
MPFR_CLEAR_FLAGS(a); |
| an = (preca-1)/BITS_PER_MP_LIMB + 1; |
MPFR_SET_NAN(a); |
| sh = an * BITS_PER_MP_LIMB - preca; |
MPFR_RET_NAN; |
| if ((*ap >> sh) & 1) { |
|
| fprintf(stderr, "unable to round in mpfr_set\n"); exit(1); |
|
| } |
} |
| mpn_rshift(ap, ap, an, 1); |
|
| ap[an-1] |= (mp_limb_t) 1 << (BITS_PER_MP_LIMB-1); |
if (MPFR_IS_INF(b)) |
| EXP(a)++; |
{ |
| } |
MPFR_CLEAR_FLAGS(a); |
| if (SIGN(a) != signb) CHANGE_SIGN(a); |
MPFR_SET_INF(a); |
| |
inex = 0; |
| |
} |
| |
else |
| |
{ |
| |
mp_limb_t *ap; |
| |
mp_prec_t aq; |
| |
int carry; |
| |
|
| |
MPFR_CLEAR_FLAGS(a); |
| |
|
| |
ap = MPFR_MANT(a); |
| |
aq = MPFR_PREC(a); |
| |
|
| |
carry = mpfr_round_raw(ap, MPFR_MANT(b), MPFR_PREC(b), (signb < 0), |
| |
aq, rnd_mode, &inex); |
| |
MPFR_EXP(a) = MPFR_EXP(b); |
| |
|
| |
if (carry) |
| |
{ |
| |
mp_exp_t exp = MPFR_EXP(a); |
| |
|
| |
if (exp == __mpfr_emax) |
| |
return mpfr_set_overflow(a, rnd_mode, signb); |
| |
|
| |
MPFR_EXP(a)++; |
| |
ap[(MPFR_PREC(a)-1)/BITS_PER_MP_LIMB] = GMP_LIMB_HIGHBIT; |
| |
} |
| |
} |
| |
|
| |
if (MPFR_SIGN(a) * signb < 0) |
| |
MPFR_CHANGE_SIGN(a); |
| |
MPFR_RET(inex); |
| } |
} |