An algorithm and hardware structure is described for numerical operations on signals that is reconfigurable to operate in a downsampling or non-downsampling mode. According to one embodiment, a plurality of adders and multipliers are reconfigurable via a switching fabric to operate as a plurality of MAAC ( multiply-add-accumulator) kernels (described in detail below), when operating in a non-downsampling mode and a plurality of MAAC kernels and AMAAC (add-multiply-add-accumulator) kernals (described in detail below), when operating in a downsampling mode.