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-rw-r--r--src/math/e_cosh.c82
1 files changed, 0 insertions, 82 deletions
diff --git a/src/math/e_cosh.c b/src/math/e_cosh.c
deleted file mode 100644
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--- a/src/math/e_cosh.c
+++ /dev/null
@@ -1,82 +0,0 @@
-
-/* @(#)e_cosh.c 1.3 95/01/18 */
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunSoft, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice 
- * is preserved.
- * ====================================================
- */
-
-/* cosh(x)
- * Method : 
- * mathematically cosh(x) if defined to be (exp(x)+exp(-x))/2
- *      1. Replace x by |x| (cosh(x) = cosh(-x)). 
- *      2. 
- *                                                      [ exp(x) - 1 ]^2 
- *          0        <= x <= ln2/2  :  cosh(x) := 1 + -------------------
- *                                                         2*exp(x)
- *
- *                                                exp(x) +  1/exp(x)
- *          ln2/2    <= x <= 22     :  cosh(x) := -------------------
- *                                                        2
- *          22       <= x <= lnovft :  cosh(x) := exp(x)/2 
- *          lnovft   <= x <= ln2ovft:  cosh(x) := exp(x/2)/2 * exp(x/2)
- *          ln2ovft  <  x           :  cosh(x) := huge*huge (overflow)
- *
- * Special cases:
- *      cosh(x) is |x| if x is +INF, -INF, or NaN.
- *      only cosh(0)=1 is exact for finite x.
- */
-
-#include <math.h>
-#include "math_private.h"
-
-static const double one = 1.0, half=0.5, huge = 1.0e300;
-
-double
-cosh(double x)
-{
-        double t,w;
-        int32_t ix;
-        uint32_t lx;
-
-    /* High word of |x|. */
-        GET_HIGH_WORD(ix,x);
-        ix &= 0x7fffffff;
-
-    /* x is INF or NaN */
-        if(ix>=0x7ff00000) return x*x;  
-
-    /* |x| in [0,0.5*ln2], return 1+expm1(|x|)^2/(2*exp(|x|)) */
-        if(ix<0x3fd62e43) {
-            t = expm1(fabs(x));
-            w = one+t;
-            if (ix<0x3c800000) return w;        /* cosh(tiny) = 1 */
-            return one+(t*t)/(w+w);
-        }
-
-    /* |x| in [0.5*ln2,22], return (exp(|x|)+1/exp(|x|)/2; */
-        if (ix < 0x40360000) {
-                t = exp(fabs(x));
-                return half*t+half/t;
-        }
-
-    /* |x| in [22, log(maxdouble)] return half*exp(|x|) */
-        if (ix < 0x40862E42)  return half*exp(fabs(x));
-
-    /* |x| in [log(maxdouble), overflowthresold] */
-        GET_LOW_WORD(lx,x);
-        if (ix<0x408633CE ||
-              ((ix==0x408633ce)&&(lx<=(uint32_t)0x8fb9f87d))) {
-            w = exp(half*fabs(x));
-            t = half*w;
-            return t*w;
-        }
-
-    /* |x| > overflowthresold, cosh(x) overflow */
-        return huge*huge;
-}