import newlib-2000-02-17 snapshot

1 files changed, 93 insertions, 0 deletions

diff --git a/newlib/libm/mathfp/s_acos.c b/newlib/libm/mathfp/s_acos.c
new file mode 100644
index 000000000..e03344e7d
--- /dev/null
+++ b/newlib/libm/mathfp/s_acos.c
@@ -0,0 +1,93 @@
+
+/* @(#)z_acos.c 1.0 98/08/13 */
+
+/*
+FUNCTION
+        <<acos>>, <<acosf>>---arc cosine
+
+INDEX
+        acos
+INDEX
+        acosf
+
+ANSI_SYNOPSIS
+        #include <math.h>
+        double acos(double <[x]>);
+        float acosf(float <[x]>);
+
+TRAD_SYNOPSIS
+        #include <math.h>
+        double acos(<[x]>)
+        double <[x]>;
+
+        float acosf(<[x]>)
+        float <[x]>;
+
+
+
+DESCRIPTION
+
+        <<acos>> computes the inverse cosine (arc cosine) of the input value.
+        Arguments to <<acos>> must be in the range @minus{}1 to 1.
+
+        <<acosf>> is identical to <<acos>>, except that it performs
+        its calculations on <<floats>>.
+
+RETURNS
+        @ifinfo
+        <<acos>> and <<acosf>> return values in radians, in the range of 0 to pi
+.
+        @end ifinfo
+        @tex
+        <<acos>> and <<acosf>> return values in radians, in the range of <<0>> t
+o $\pi$.
+        @end tex
+
+        If <[x]> is not between @minus{}1 and 1, the returned value is NaN
+        (not a number) the global variable <<errno>> is set to <<EDOM>>, and a
+        <<DOMAIN error>> message is sent as standard error output.
+
+        You can modify error handling for these functions using <<matherr>>.
+
+
+QUICKREF ANSI SVID POSIX RENTRANT
+ acos    y,y,y,m
+ acosf   n,n,n,m
+
+MATHREF
+ acos, [-1,1], acos(arg),,,
+ acos, NAN,    arg,DOMAIN,EDOM
+
+MATHREF
+ acosf, [-1,1], acosf(arg),,,
+ acosf, NAN,    argf,DOMAIN,EDOM
+
+*/
+
+/*****************************************************************
+ * Arccosine
+ *
+ * Input:
+ *   x - floating point value
+ *
+ * Output:
+ *   arccosine of x
+ *
+ * Description:
+ *   This routine returns the arccosine of x.
+ *
+ *****************************************************************/
+
+#include "fdlibm.h"
+#include "zmath.h"
+
+#ifndef _DOUBLE_IS_32BITS
+
+double
+_DEFUN (acos, (double),
+        double x)
+{
+  return (asine (x, 1));
+}
+
+#endif /* _DOUBLE_IS_32BITS */