74 lines
1.3 KiB
C
74 lines
1.3 KiB
C
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/* @(#)s_fabs.c 5.1 93/09/24 */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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/*
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FUNCTION
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<<fabs>>, <<fabsf>>---absolute value (magnitude)
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INDEX
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fabs
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INDEX
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fabsf
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ANSI_SYNOPSIS
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#include <math.h>
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double fabs(double <[x]>);
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float fabsf(float <[x]>);
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TRAD_SYNOPSIS
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#include <math.h>
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double fabs(<[x]>)
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double <[x]>;
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float fabsf(<[x]>)
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float <[x]>;
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DESCRIPTION
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<<fabs>> and <<fabsf>> calculate
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@tex
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$|x|$,
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@end tex
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the absolute value (magnitude) of the argument <[x]>, by direct
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manipulation of the bit representation of <[x]>.
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RETURNS
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The calculated value is returned. No errors are detected.
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PORTABILITY
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<<fabs>> is ANSI.
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<<fabsf>> is an extension.
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*/
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/*
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* fabs(x) returns the absolute value of x.
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*/
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#include "fdlibm.h"
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#ifndef _DOUBLE_IS_32BITS
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#ifdef __STDC__
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double fabs(double x)
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#else
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double fabs(x)
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double x;
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#endif
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{
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__uint32_t high;
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GET_HIGH_WORD(high,x);
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SET_HIGH_WORD(x,high&0x7fffffff);
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return x;
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}
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#endif /* _DOUBLE_IS_32BITS */
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