According to the theory established, to describe this phenomenon, one must consider the complex quantity of magnetic susceptibility: k = k' + ik", in order to take into account the effect of the eddy current influence on the phase shift in relation to the energy losses inside the material constituting the core sample [18].

The coil impedance is a complex quantity written as Z = R + iL[omega].

In the present paper, I propose a straightforward method to convert the spectrum of arbitrary complex quantity z into its reciprocal 1/z based on the graphical procedure on ColeCole diagram.

Although both [C.sup.*.sub.g]([omega]) and [M.sup.*]([omega]) can be plotted onto the Cole-Cole diagram as the complex quantity z, only the former situation is to be described in the following discussion to avoid redundancy.