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diff --git a/lib/libm/src/s_cpowf.c b/lib/libm/src/s_cpowf.c
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+/*	$OpenBSD: s_cpowf.c,v 1.1 2008/09/07 20:36:09 martynas Exp $	*/
+/*
+ * Copyright (c) 2008 Stephen L. Moshier <steve@moshier.net>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, 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.
+ */
+
+/*							cpowf
+ *
+ *	Complex power function
+ *
+ *
+ *
+ * SYNOPSIS:
+ *
+ * float complex cpowf();
+ * float complex a, z, w;
+ *
+ * w = cpowf (a, z);
+ *
+ *
+ *
+ * DESCRIPTION:
+ *
+ * Raises complex A to the complex Zth power.
+ * Definition is per AMS55 # 4.2.8,
+ * analytically equivalent to cpow(a,z) = cexp(z clog(a)).
+ *
+ * ACCURACY:
+ *
+ *                      Relative error:
+ * arithmetic   domain     # trials      peak         rms
+ *    IEEE      -10,+10     30000       9.4e-15     1.5e-15
+ *
+ */
+
+#include <complex.h>
+#include <math.h>
+
+float complex
+cpowf(float complex a, float complex z)
+{
+	float complex w;
+	float x, y, r, theta, absa, arga;
+
+	x = creal (z);
+	y = cimag (z);
+	absa = cabsf (a);
+	if (absa == 0.0f) {
+		return (0.0f + 0.0f * I);
+	}
+	arga = cargf (a);
+	r = powf (absa, x);
+	theta = x * arga;
+	if (y != 0.0f) {
+		r = r * expf (-y * arga);
+		theta = theta + y * logf (absa);
+	}
+	w = r * cosf (theta) + (r * sinf (theta)) * I;
+	return (w);
+}