Tenreiro Machado, J. A.Galhano, Alexandra2019-04-042019-04-042008-06http://hdl.handle.net/10400.22/13386This paper addresses the calculation of fractional derivatives of fractional order for non-smooth data. The noise is avoided by adopting an optimization formulation using genetic algorithms (GA). Given the flexibility of the evolutionary schemes it is established a hierarchical GA composed by a series of two GAs, each one with having a distinct fitness function.engFractional calculusNumerical differentiationGenetic algorithmsconference object