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/*
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	sinh(arg) returns the hyperbolic sine of its floating-
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	point argument.
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	The exponential function is called for arguments
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	greater in magnitude than 0.5.
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	A series is used for arguments smaller in magnitude than 0.5.
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	The coefficients are #2029 from Hart & Cheney. (20.36D)
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	cosh(arg) is computed from the exponential function for
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	all arguments.
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*/
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#include <math.h>
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#include <errno.h>
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static double p0  = -0.6307673640497716991184787251e+6;
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static double p1  = -0.8991272022039509355398013511e+5;
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static double p2  = -0.2894211355989563807284660366e+4;
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static double p3  = -0.2630563213397497062819489e+2;
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static double q0  = -0.6307673640497716991212077277e+6;
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static double q1   = 0.1521517378790019070696485176e+5;
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static double q2  = -0.173678953558233699533450911e+3;
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double
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sinh(double arg)
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{
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	double temp, argsq;
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	int sign;
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	sign = 1;
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	if(arg < 0) {
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		arg = - arg;
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		sign = -1;
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	}
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	if(arg > 21) {
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		if(arg >= HUGE_VAL){
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			errno = ERANGE;
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			temp = HUGE_VAL;
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		} else
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			temp = exp(arg)/2;
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		if(sign > 0)
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			return temp;
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		else
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			return -temp;
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	}
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	if(arg > 0.5)
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		return sign*(exp(arg) - exp(-arg))/2;
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	argsq = arg*arg;
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	temp = (((p3*argsq+p2)*argsq+p1)*argsq+p0)*arg;
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	temp /= (((argsq+q2)*argsq+q1)*argsq+q0);
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	return sign*temp;
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}
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double
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cosh(double arg)
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{
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	if(arg < 0)
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		arg = - arg;
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	if(arg > 21) {
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		if(arg >= HUGE_VAL){
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			errno = ERANGE;
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			return HUGE_VAL;
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		} else
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			return(exp(arg)/2);
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	}
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	return (exp(arg) + exp(-arg))/2;
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}