When forming metallic components, in particular three-dimensionally curved blades, which constitute a single piece with the blading of turbomachine rotor wheels, the linear oscillation of the electrode acting as a tool is superimposed by a circular oscillation, enabling the electrode to turn into the workpiece conformally with its shape. One method comprises reading a group of non-volatile storage elements on a memory die at a first set of read levels. The system then constructs a first sketch vector with n elements based on the combined hash results. The resultant data pattern provides a third harmonic with a relatively high magnitude and improved signal to noise ratio.