2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/207048We describe a simple implementation of black hole excision in 3+1 numerical relativity. We apply this technique to a Schwarzschild black hole with octant symmetry in Eddington-Finkelstein coordinates and show how one can obtain accurate, long-term stable numerical evolutions.7 pages, 7 figures, revtex. Incorporates comments made by refereeGeneral Relativity and Quantum Cosmologytext