52 lines
1.6 KiB
C
52 lines
1.6 KiB
C
/***********************************************************
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Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
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Amsterdam, The Netherlands.
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All Rights Reserved
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Permission to use, copy, modify, and distribute this software and its
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documentation for any purpose and without fee is hereby granted,
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provided that the above copyright notice appear in all copies and that
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both that copyright notice and this permission notice appear in
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supporting documentation, and that the names of Stichting Mathematisch
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Centrum or CWI not be used in advertising or publicity pertaining to
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distribution of the software without specific, written prior permission.
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STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
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THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
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FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
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FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
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WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
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ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
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OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
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******************************************************************/
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/* Portable fmod(x, y) implementation for systems that don't have it */
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#include <math.h>
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#include <errno.h>
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extern int errno;
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double
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fmod(x, y)
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double x, y;
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{
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double i, f;
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if (y == 0.0) {
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errno = EDOM;
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return 0.0;
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}
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/* return f such that x = i*y + f for some integer i
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such that |f| < |y| and f has the same sign as x */
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i = floor(x/y);
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f = x - i*y;
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if ((x < 0.0) != (y < 0.0))
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f = f-y;
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return f;
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}
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