  Computation of the simplicial complexes of a large point cloud often relies
on extracting a sample, to reduce the associated computational burden. The
study considers sampling critical points of a Morse function associated to a
point cloud, to approximate the Vietoris-Rips complex or the witness complex
and compute persistence homology. The effectiveness of the novel approach is
compared with the farthest point sampling, in a context of classifying human
face images into ethnics groups using persistence homology.
