The relations among the various elements of a conductance matrix may be expressed in certain fotms of inequalities

These inequalities are different for conductance matrices corresponding to different trees of the ports. In this paper these inequalities are fullydiscussed

and several important theorems concerning them are derived. When the tree ofthe ports corresponding to a given condu6tance matrix of order n is determined from itssign matrix

the application of these theorems will yield the conditions for realizability of the given matrix with an n+1 node network.