A variational method of calculating the sensitivity coefficients (comp
onents of the gradient of a quality index for constant parameters) for
multidimensional nonlinear dynamic systems described by ordinary diff
erential equations with a discontinuous right side and discontinuous p
hase coordinates is designed, The solution of corresponding adjoint eq
uations is the inverse time direction is the basis of the calculation.
Adjoint equations are also ordinary differential equations with disco
ntinuous right side and with discontinuous phase coordinates.