__kernel_cos
case 2: y = __kernel_cos(pi*(0.5-y),zero); break;
case 6: y = -__kernel_cos(pi*(y-1.5),zero); break;
return (__kernel_cos(hi, lo));
double __kernel_cos(double,double);
return __kernel_cos(x,z);
case 0: return __kernel_cos(y[0],y[1]);
case 2: return -__kernel_cos(y[0],y[1]);
case 1: return __kernel_cos(y[0],y[1]);
return -__kernel_cos(y[0],y[1]);