We treat radiation trapping in a saturated atomic vapor in a cylindric
al vapor cell. When saturation (i.e. stimulated emission) sets in, the
Holstein equation of radiation trapping becomes nonlinear, and the ab
sorption coefficient can become inhomogeneous. We first present a new
method for the efficient computation of the reabsorption rate with an
inhomogeneous distribution of absorbers in a cylinder. We then use thi
s method as the basis of an algorithm for the computation of trapping
in a saturated vapor.