Network invariant sensitivity sums

New theorems on network sensitivities are derived for a general lumped time-invariant (LTI) network containing passive and active elements. The sums of the numerator and denominator sensitivities of network functions are given. The sums of numerator and denominator coefficient sensitivities are also developed. These studies are extended to include pole and zero, and and sensitivity sums. The results are very useful in the step-by-step checking and debugging of network sensitivity computations. In the case of symbolic generation of network functions, the sum of numerator and denominator coefficient sensitivities can be used to check the correctnessof the expressions obtained.