108 lines
2.3 KiB
C
108 lines
2.3 KiB
C
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/* @(#)w_fmod.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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<<fmod>>, <<fmodf>>---floating-point remainder (modulo)
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INDEX
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fmod
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INDEX
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fmodf
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ANSI_SYNOPSIS
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#include <math.h>
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double fmod(double <[x]>, double <[y]>);
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float fmodf(float <[x]>, float <[y]>);
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TRAD_SYNOPSIS
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#include <math.h>
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double fmod(<[x]>, <[y]>);
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double (<[x]>, <[y]>);
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float fmodf(<[x]>, <[y]>);
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float (<[x]>, <[y]>);
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DESCRIPTION
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The <<fmod>> and <<fmodf>> functions compute the floating-point
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remainder of <[x]>/<[y]> (<[x]> modulo <[y]>).
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RETURNS
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The <<fmod>> function returns the value
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@ifnottex
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<[x]>-<[i]>*<[y]>,
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@end ifnottex
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@tex
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$x-i\times y$,
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@end tex
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for the largest integer <[i]> such that, if <[y]> is nonzero, the
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result has the same sign as <[x]> and magnitude less than the
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magnitude of <[y]>.
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<<fmod(<[x]>,0)>> returns NaN, and sets <<errno>> to <<EDOM>>.
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You can modify error treatment for these functions using <<matherr>>.
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PORTABILITY
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<<fmod>> is ANSI C. <<fmodf>> is an extension.
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*/
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/*
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* wrapper fmod(x,y)
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*/
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#include "fdlibm.h"
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#include <errno.h>
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#ifndef _DOUBLE_IS_32BITS
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#ifdef __STDC__
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double fmod(double x, double y) /* wrapper fmod */
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#else
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double fmod(x,y) /* wrapper fmod */
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double x,y;
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#endif
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{
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#ifdef _IEEE_LIBM
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return __ieee754_fmod(x,y);
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#else
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double z;
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struct exception exc;
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z = __ieee754_fmod(x,y);
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if(_LIB_VERSION == _IEEE_ ||isnan(y)||isnan(x)) return z;
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if(y==0.0) {
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/* fmod(x,0) */
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exc.type = DOMAIN;
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exc.name = "fmod";
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exc.arg1 = x;
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exc.arg2 = y;
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exc.err = 0;
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if (_LIB_VERSION == _SVID_)
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exc.retval = x;
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else
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exc.retval = 0.0/0.0;
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if (_LIB_VERSION == _POSIX_)
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errno = EDOM;
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else if (!matherr(&exc)) {
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errno = EDOM;
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}
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if (exc.err != 0)
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errno = exc.err;
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return exc.retval;
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} else
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return z;
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#endif
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}
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#endif /* defined(_DOUBLE_IS_32BITS) */
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