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-rw-r--r--sysdeps/generic/s_casin.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/sysdeps/generic/s_casin.c b/sysdeps/generic/s_casin.c
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+++ b/sysdeps/generic/s_casin.c
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+/* Return arc sine of complex double value.
+   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 Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; 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>
+
+
+__complex__ double
+__casin (__complex__ double x)
+{
+  __complex__ double res;
+
+  if (isnan (__real__ x) || isnan (__imag__ x))
+    {
+      if (__real__ x == 0.0)
+	{
+	  res = x;
+	}
+      else if (__isinf (__real__ x) || __isinf (__imag__ x))
+	{
+	  __real__ res = __nan ("");
+	  __imag__ res = __copysign (HUGE_VAL, __imag__ x);
+	}
+      else
+	{
+	  __real__ res = __nan ("");
+	  __imag__ res = __nan ("");
+	}
+    }
+  else
+    {
+      __complex__ double y;
+
+      __real__ y = -__imag__ x;
+      __imag__ y = __real__ x;
+
+      y = __casinh (y);
+
+      __real__ res = __imag__ y;
+      __imag__ res = -__real__ y;
+    }
+
+  return res;
+}
+weak_alias (__casin, casin)
+#ifdef NO_LONG_DOUBLE
+strong_alias (__casin, __casinl)
+weak_alias (__casin, casinl)
+#endif