double y0(double x);
double y1(double x);
double yn(int, double);

These functions compute Bessel functions of the second kind. y0 and y1 compute the functions of order 0 and 1 respectively. yn computes the function of order n.

If x is positive and exceeds π times 2⁵², these functions return an ERANGE error, denoting total loss of significance in the result.