Problems with overflow with Bessel

I'm working on simulation of whispering gallery mode and i need to calculate the field inside some microresonators using Bessel and Hankel functions and their derivatives.

Everything works until i tried to evaluate this function for some nu,Z values.

In some cases i have found -Inf, +Inf or 0.

E.g.

spherical_besselj(400,100)

ans =

      5.036580472507386e-194

spherical_besselj(600,100)

ans =

      0

This is very frustrating for me because this limits my simulations in a range of values too small.

Can you help me?

Can someone let me understand the problem?

Is there a way to prevent this problems?

Thank you very much

Andrea

[Walter Roberson]

You might need to switch to the Symbolic Toolbox