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-rw-r--r--math/s_casin.c66
1 files changed, 66 insertions, 0 deletions
diff --git a/math/s_casin.c b/math/s_casin.c
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+++ b/math/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