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