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-rw-r--r--sysdeps/libm-ieee754/s_clogf.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_clogf.c b/sysdeps/libm-ieee754/s_clogf.c
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+/* Compute complex natural logarithm.
+   Copyright (C) 1997 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Library General Public License as
+   published by the Free Software Foundation; either version 2 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <complex.h>
+#include <math.h>
+
+#include "math_private.h"
+
+
+__complex__ float
+__clogf (__complex__ float x)
+{
+  __complex__ float result;
+
+  if (__real__ x == 0.0 && __imag__ x == 0.0)
+    {
+      __imag__ result = signbit (__real__ x) ? M_PI : 0.0;
+      if (signbit (__imag__ x))
+	__imag__ result = __copysignf (__imag__ result, -1.0);
+      /* Yes, the following line raises an exception.  */
+      __real__ result = -1.0 / fabsf (__real__ x);
+    }
+  else  if (!__isnanf (__real__ x) && !__isnanf (__imag__ x))
+    {
+      __real__ result = __ieee754_logf (__ieee754_hypotf (__real__ x,
+							  __imag__ x));
+      __imag__ result = __ieee754_atan2f (__imag__ x, __real__ x);
+    }
+  else
+    {
+      __imag__ result = __nanf ("");
+      if (__isinff (__real__ x) || __isinff (__imag__ x))
+	__real__ result = HUGE_VALF;
+      else
+	__real__ result = __nanf ("");
+    }
+
+  return result;
+}
+weak_alias (__clogf, clogf)