about summary refs log tree commit diff
path: root/sysdeps/libm-ieee754/s_ctanf.c
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/libm-ieee754/s_ctanf.c')
-rw-r--r--sysdeps/libm-ieee754/s_ctanf.c60
1 files changed, 60 insertions, 0 deletions
diff --git a/sysdeps/libm-ieee754/s_ctanf.c b/sysdeps/libm-ieee754/s_ctanf.c
new file mode 100644
index 0000000000..99011fa41d
--- /dev/null
+++ b/sysdeps/libm-ieee754/s_ctanf.c
@@ -0,0 +1,60 @@
+/* Complex tangent function for float.
+   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
+__ctanf (__complex__ float x)
+{
+  __complex__ float res;
+
+  if (!finite (__real__ x) || !finite (__imag__ x))
+    {
+      if (__isinff (__imag__ x))
+	{
+	  __real__ res = __copysignf (0.0, __real__ x);
+	  __imag__ res = __copysignf (1.0, __imag__ x);
+	}
+      else if (__real__ x == 0.0)
+	{
+	  res = x;
+	}
+      else
+	{
+	  __real__ res = __nanf ("");
+	  __imag__ res = __nanf ("");
+	}
+    }
+  else
+    {
+      float den = (__cosf (2.0 * __real__ x)
+		   + __ieee754_coshf (2.0 * __imag__ x));
+
+      __real__ res = __sinf (2.0 * __real__ x) / den;
+      __imag__ res = __ieee754_sinhf (2.0 * __imag__ x) / den;
+    }
+
+  return res;
+}
+weak_alias (__ctanf, ctanf)