Before revision:  For example, we show how to approximate the Smallest Enclosing Ball (SEB) of a set of complex  matrices in the Siegel  domains: We compare two implementations of a generalization of the iterative  algorithm of [Badoiu and Clarkson, 2003] in the Siegel-Poincar\'e disk and in the Siegel-Klein disk.
After revision:  As an illustrating example, we show how to approximate the Smallest Enclosing Ball (SEB) of a set of complex matrices in the Siegel domains: We compare two implementations of a generalization of the iterative algorithm of [Badoiu and Clarkson, 2003] in the Siegel-Poincar\'e disk and in the Siegel-Klein disk.