efee5258bc
The MPFR library is a C library for multiple-precision floating-point computations with exact rounding (also called correct rounding). It is based on the GMP multiple-precision library and should replace the MPF class in further releases of GMP. GCC >= 4.2 requires MPFR.
39 lines
1.5 KiB
C
39 lines
1.5 KiB
C
/* mpfr_copysign -- Produce a value with the magnitude of x and sign bit of y
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Copyright 2001, 2002, 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
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Contributed by the Arenaire and Cacao projects, INRIA.
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This file is part of the GNU MPFR Library.
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The GNU MPFR Library is free software; you can redistribute it and/or modify
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it under the terms of the GNU Lesser General Public License as published by
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the Free Software Foundation; either version 3 of the License, or (at your
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option) any later version.
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The GNU MPFR Library is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
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or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
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License for more details.
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You should have received a copy of the GNU Lesser General Public License
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along with the GNU MPFR Library; see the file COPYING.LESSER. If not, see
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http://www.gnu.org/licenses/ or write to the Free Software Foundation, Inc.,
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51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. */
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#include "mpfr-impl.h"
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/*
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The computation of z with magnitude of x and sign of y:
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z = (-1)^signbit(y) * abs(x), i.e. with the same sign bit as y,
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even if z is a NaN.
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Note: This function implements copysign from the IEEE-754 standard
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when no rounding occurs (e.g. if PREC(z) >= PREC(x)).
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*/
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#undef mpfr_copysign
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int
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mpfr_copysign (mpfr_ptr z, mpfr_srcptr x, mpfr_srcptr y, mpfr_rnd_t rnd_mode)
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{
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return mpfr_set4 (z, x, rnd_mode, MPFR_SIGN (y));
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}
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