54 lines
1.3 KiB
C
54 lines
1.3 KiB
C
/* Multiply a 'float' by a power of 2.
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Copyright 2002-2003, 2007-2024 Free Software Foundation, Inc.
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This file 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
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published by the Free Software Foundation; either version 2.1 of the
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License, or (at your option) any later version.
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This file is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Lesser General Public 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 this program. If not, see <https://www.gnu.org/licenses/>. */
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/* Written by Paolo Bonzini and Bruno Haible. */
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#include <config.h>
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/* Specification. */
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#include <math.h>
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/* Avoid some warnings from "gcc -Wshadow".
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This file doesn't use the exp() function. */
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#undef exp
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#define exp exponent
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#if HAVE_SAME_LONG_DOUBLE_AS_DOUBLE
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long double
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ldexpl (long double x, int exp)
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{
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return ldexp (x, exp);
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}
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#else
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# define USE_LONG_DOUBLE
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# include "ldexp.c"
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#endif
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#if 0
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int
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main (void)
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{
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long double x;
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int y;
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for (y = 0; y < 29; y++)
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printf ("%5d %.16Lg %.16Lg\n", y, ldexpl (0.8L, y), ldexpl (0.8L, -y) * ldexpl (0.8L, y));
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}
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#endif
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