The circuit determinant \(\Delta\) is the determinant of the matrix description of the circuit. The latter is the matrix form of a general cutset of the circuit. In particular:
- The mesh equations, in which the driving sources are voltages.
- The nodal equations, in which the driving sources are currents.
- The indefinite admittance matrix, defined by Chen.
The determinant is not invariant among these different formulations, however, each one features the same roots (poles of the circuit) if it describes the same circuit.