1. Apparatus for processing an analog waveform, said analog waveform having a first component, said apparatus comprising: means for converting said analog waveform into a digital signal having a first set of digital values; calculator means receiving a sequence of input values which define an argument of a Portmanteau function generator equation for creating a second set of digital values each comprising a calculated result of said Portmanteau function generator equation and said argument; and means for combining said second set of digital values with said first set of digital values to produce a modified set of digital values representing a modified version of said analog waveform, thereby removing said first component.