Properties of constitutive matrices for electrostatic and magnetostatic problems

Constitutive matrices allow one to write the constitutive relations, in an algebraic form, in some finite-volume-based numerical methods, such as the cell method and the finite integration technique. This paper shows some properties that link a general class of constitutive matrices to the finite-element stiffness matrices. One of these properties can be exploited to provide an alternative sufficient condition for the stability of a generalized finite-difference time-domain algorithm set up by these numerical methods.