import newlib-2000-02-17 snapshot

1 files changed, 140 insertions, 0 deletions

diff --git a/newlib/libm/math/w_atanh.c b/newlib/libm/math/w_atanh.c
new file mode 100644
index 000000000..b89d4f025
--- /dev/null
+++ b/newlib/libm/math/w_atanh.c
@@ -0,0 +1,140 @@
+
+/* @(#)w_atanh.c 5.1 93/09/24 */
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice 
+ * is preserved.
+ * ====================================================
+ */
+
+/*
+FUNCTION
+	<<atanh>>, <<atanhf>>---inverse hyperbolic tangent 
+
+INDEX
+	atanh
+INDEX
+	atanhf
+
+ANSI_SYNOPSIS
+	#include <math.h>
+	double atanh(double <[x]>);
+	float atanhf(float <[x]>);
+
+TRAD_SYNOPSIS
+	#include <math.h>
+	double atanh(<[x]>)
+	double <[x]>;
+
+	float atanhf(<[x]>)
+	float <[x]>;
+
+DESCRIPTION
+	<<atanh>> calculates the inverse hyperbolic tangent of <[x]>.
+
+	<<atanhf>> is identical, other than taking and returning
+	<<float>> values.
+
+RETURNS
+	<<atanh>> and <<atanhf>> return the calculated value.
+
+	If 
+	@ifinfo
+	|<[x]>|
+	@end ifinfo
+	@tex
+	$|x|$
+	@end tex
+	is greater than 1, the global <<errno>> is set to <<EDOM>> and
+	the result is a NaN.  A <<DOMAIN error>> is reported.
+
+	If 
+	@ifinfo
+	|<[x]>|
+	@end ifinfo
+	@tex
+	$|x|$
+	@end tex
+	is 1, the global <<errno>> is set to <<EDOM>>; and the result is 
+	infinity with the same sign as <<x>>.  A <<SING error>> is reported.
+
+	You can modify the error handling for these routines using
+	<<matherr>>.
+
+PORTABILITY
+	Neither <<atanh>> nor <<atanhf>> are ANSI C.
+
+QUICKREF
+	atanh - pure
+	atanhf - pure
+
+
+*/
+
+/* 
+ * wrapper atanh(x)
+ */
+
+#include "fdlibm.h"
+#include <errno.h>
+
+#ifndef _DOUBLE_IS_32BITS
+
+#ifdef __STDC__
+	double atanh(double x)		/* wrapper atanh */
+#else
+	double atanh(x)			/* wrapper atanh */
+	double x;
+#endif
+{
+#ifdef _IEEE_LIBM
+	return __ieee754_atanh(x);
+#else
+	double z,y;
+	struct exception exc;
+	z = __ieee754_atanh(x);
+	if(_LIB_VERSION == _IEEE_ || isnan(x)) return z;
+	y = fabs(x);
+	if(y>=1.0) {
+	    if(y>1.0) {
+                /* atanh(|x|>1) */
+                exc.type = DOMAIN;
+                exc.name = "atanh";
+		exc.err = 0;
+		exc.arg1 = exc.arg2 = x;
+                exc.retval = 0.0/0.0;
+                if (_LIB_VERSION == _POSIX_)
+                  errno = EDOM;
+                else if (!matherr(&exc)) {
+                  errno = EDOM;
+                }
+	    } else { 
+                /* atanh(|x|=1) */
+                exc.type = SING;
+                exc.name = "atanh";
+		exc.err = 0;
+		exc.arg1 = exc.arg2 = x;
+		exc.retval = x/0.0;	/* sign(x)*inf */
+                if (_LIB_VERSION == _POSIX_)
+                  errno = EDOM;
+                else if (!matherr(&exc)) {
+                  errno = EDOM;
+                }
+            }
+	    if (exc.err != 0)
+              errno = exc.err;
+            return exc.retval; 
+	} else
+	    return z;
+#endif
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */
+
+
+
+