“…Recent investigations in computational physics and numerical simulations have focused their attentions in the development of techniques to approximate propagating wave solutions in several media [9], including the wave equation itself [3]. On the other hand, several numerical methods have been developed in order to preserve the positivity of the solutions of some differential equations via non-standard techniques [2,8,[20][21][22]24,27,30]. However, the problem of designing positivity-preserving, finite-difference schemes to approximate nonnegative solutions of nonlinear, hyperbolic generalizations of the Fisher-KPP equations has not been successfully solved, yet.…”