.TRANSFORM.Nuclear.ReactorKinetics.SparseMatrix.PointKinetics_L1_powerBased_sparseMatrix.Reactivity .TRANSFORM.Nuclear.ReactorKinetics.SparseMatrix.PointKinetics_L1_powerBased_sparseMatrix.Reactivitymodel Reactivity = TRANSFORM.Nuclear.ReactorKinetics.SparseMatrix.Reactivity.Isotopes.Lumped.Isotopes_sparseMatrix;