Maxima Function
scaled_bessel_i (v, z)
The scaled modified Bessel function of the first kind of order
v and argument z. That is, scaled_bessel_i(v,z) =exp(-abs(z))*bessel_i(v, z). This function is particularly useful
for calculating bessel_i for large z, which is large.
However, maxima does not otherwise know much about this function. For
symbolic work, it is probably preferable to work with the expression
exp(-abs(z))*bessel_i(v, z)
.