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+/*
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+ * (c) copyright 1988 by the Vrije Universiteit, Amsterdam, The Netherlands.
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+ * See the copyright notice in the ACK home directory, in the file "Copyright".
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+ *
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+ * Author: Ceriel J.H. Jacobs
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+ */
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+
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+#include <math.h>
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+
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+/* $Header$ */
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+
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+double
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+hypot(double x,double y)
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+{
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+ /* Computes sqrt(x*x+y*y), avoiding overflow */
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+
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+ if (x < 0) x = -x;
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+ if (y < 0) y = -y;
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+ if (x > y) {
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+ double t = y;
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+ y = x;
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+ x = t;
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+ }
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+ /* sqrt(x*x+y*y) = sqrt(y*y*(x*x/(y*y)+1.0)) = y*sqrt(x*x/(y*y)+1.0) */
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+ if (y == 0.0) return 0.0;
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+ x /= y;
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+ return y*sqrt(x*x+1.0);
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+}
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+
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+struct complex {
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+ double r,i;
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+};
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+
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+double
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+cabs(struct complex p_compl)
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+{
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+ return hypot(p_compl.r, p_compl.i);
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+}
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