Bessel_y1

Definition:

$y1 = bessel\_y1(x)$ evaluates the Bessel function of the second kind, $Y_1$ , x > 0.

The approximation is based on Chebyshev expansions.

For more information please review the s17adc function in the NAG document.

x (input, double): The argument x of the function.; Constraint: x>0.0
$y1$ (output, double): The approximation of the Bessel function of the second kind.