/* * asin(arg) and acos(arg) return the arcsin, arccos, * respectively of their arguments. * * Arctan is called after appropriate range reduction. */ #include <u.h>#include <libc.h> doubleasin(double arg){	double temp;	int sign; 	sign = 0;	if(arg < 0) {		arg = -arg;		sign++;	}	if(arg > 1)		return NaN();	temp = sqrt(1 - arg*arg);	if(arg > 0.7)		temp = PIO2 - atan(temp/arg);	else		temp = atan(arg/temp);	if(sign)		temp = -temp;	return temp;} doubleacos(double arg){	if(arg > 1 || arg < -1)		return NaN();	return PIO2 - asin(arg);}