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/* |
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* ==================================================== |
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. |
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* |
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* Developed at SunPro, a Sun Microsystems, Inc. business. |
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* Permission to use, copy, modify, and distribute this |
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* software is freely granted, provided that this notice |
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* is preserved. |
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* ==================================================== |
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*/ |
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<>, <>---hyperbolic cosine |
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#include |
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double cosh(double <[x]>); |
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float coshf(float <[x]>) |
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#include |
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double cosh(<[x]>) |
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double <[x]>; |
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float <[x]>; |
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<)>> is defined as |
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@ifnottex |
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. (exp(x) + exp(-x))/2 |
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@end ifnottex |
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@tex |
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$${(e^x + e^{-x})} \over 2$$ |
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@end tex |
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The computed value is returned. When the correct value would create |
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an overflow, <> returns the value <> with the |
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appropriate sign, and the global value <> is set to <>. |
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function <>. |
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<> is ANSI. |
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<> is an extension. |
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cosh ansi pure |
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coshf - pure |
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*/ |
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* wrapper cosh(x) |
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*/ |
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#include |
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double cosh(double x) /* wrapper cosh */ |
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#else |
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double cosh(x) /* wrapper cosh */ |
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double x; |
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#endif |
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{ |
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#ifdef _IEEE_LIBM |
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return __ieee754_cosh(x); |
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#else |
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double z; |
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struct exception exc; |
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z = __ieee754_cosh(x); |
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if(_LIB_VERSION == _IEEE_ || isnan(x)) return z; |
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if(fabs(x)>7.10475860073943863426e+02) { |
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/* cosh(finite) overflow */ |
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#ifndef HUGE_VAL |
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#define HUGE_VAL inf |
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double inf = 0.0; |
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#endif |
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exc.type = OVERFLOW; |
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exc.name = "cosh"; |
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exc.err = 0; |
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exc.arg1 = exc.arg2 = x; |
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if (_LIB_VERSION == _SVID_) |
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exc.retval = HUGE; |
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else |
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exc.retval = HUGE_VAL; |
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if (_LIB_VERSION == _POSIX_) |
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errno = ERANGE; |
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else if (!matherr(&exc)) { |
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errno = ERANGE; |
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} |
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if (exc.err != 0) |
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errno = exc.err; |
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return exc.retval; |
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} else |
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return z; |
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#endif |
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} |
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