We show in this paper how it is possible to digitize a wide class of plane compacta in such a way that their digitization shave the same shape, in the sense of Borsuk, as the original set. This class is formed by all those compacta having the shape of finite polyhedra. As a corollary we get that for a still wide subclass, that whose elements are also absolute neighborhood retracts, the homotopy properties are also preserved under appropriate digitizations. Our results are based in approximation results by finite polyhedra and on the fact that the usual digitizations, when applied to finite polyhedra, preserve the homotopy type. Moreover, we show that if a set does not have the shape of a finite polyhedron, then there is not any possible way to digitize it while having its shape preserved.
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