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-rw-r--r--src/math/s_tanh.c74
1 files changed, 0 insertions, 74 deletions
diff --git a/src/math/s_tanh.c b/src/math/s_tanh.c
deleted file mode 100644
index 78b8e849..00000000
--- a/src/math/s_tanh.c
+++ /dev/null
@@ -1,74 +0,0 @@
-/* @(#)s_tanh.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.
- * ====================================================
- */
-
-/* Tanh(x)
- * Return the Hyperbolic Tangent of x
- *
- * Method :
- *                                     x    -x
- *                                    e  - e
- *      0. tanh(x) is defined to be -----------
- *                                     x    -x
- *                                    e  + e
- *      1. reduce x to non-negative by tanh(-x) = -tanh(x).
- *      2.  0      <= x <= 2**-55 : tanh(x) := x*(one+x)
- *                                              -t
- *          2**-55 <  x <=  1     : tanh(x) := -----; t = expm1(-2x)
- *                                             t + 2
- *                                                   2
- *          1      <= x <=  22.0  : tanh(x) := 1-  ----- ; t=expm1(2x)
- *                                                 t + 2
- *          22.0   <  x <= INF    : tanh(x) := 1.
- *
- * Special cases:
- *      tanh(NaN) is NaN;
- *      only tanh(0)=0 is exact for finite argument.
- */
-
-#include <math.h>
-#include "math_private.h"
-
-static const double one=1.0, two=2.0, tiny = 1.0e-300;
-
-double
-tanh(double x)
-{
-        double t,z;
-        int32_t jx,ix;
-
-    /* High word of |x|. */
-        GET_HIGH_WORD(jx,x);
-        ix = jx&0x7fffffff;
-
-    /* x is INF or NaN */
-        if(ix>=0x7ff00000) {
-            if (jx>=0) return one/x+one;    /* tanh(+-inf)=+-1 */
-            else       return one/x-one;    /* tanh(NaN) = NaN */
-        }
-
-    /* |x| < 22 */
-        if (ix < 0x40360000) {          /* |x|<22 */
-            if (ix<0x3c800000)          /* |x|<2**-55 */
-                return x*(one+x);       /* tanh(small) = small */
-            if (ix>=0x3ff00000) {       /* |x|>=1  */
-                t = expm1(two*fabs(x));
-                z = one - two/(t+two);
-            } else {
-                t = expm1(-two*fabs(x));
-                z= -t/(t+two);
-            }
-    /* |x| > 22, return +-1 */
-        } else {
-            z = one - tiny;             /* raised inexact flag */
-        }
-        return (jx>=0)? z: -z;
-}