def apply_linear(self, params, unknowns, dparams, dunknowns, dresids,
                     mode):
        """
        Multiplies incoming vector by the Jacobian (fwd mode) or the
        transpose Jacobian (rev mode).

        Args
        ----
        params : `VecWrapper`
            `VecWrapper` containing parameters. (p)

        unknowns : `VecWrapper`
            `VecWrapper` containing outputs and states. (u)

        dparams : `VecWrapper`
            `VecWrapper` containing either the incoming vector in forward mode
            or the outgoing result in reverse mode. (dp)

        dunknowns : `VecWrapper`
            In forward mode, this `VecWrapper` contains the incoming vector for
            the states. In reverse mode, it contains the outgoing vector for
            the states. (du)

        dresids : `VecWrapper`
            `VecWrapper` containing either the outgoing result in forward mode
            or the incoming vector in reverse mode. (dr)

        mode : string
            Derivative mode, can be 'fwd' or 'rev'.
        """

        if mode == 'fwd':
            dresids[self.out_name] += dparams[self.param_name]

        elif mode < 'rev':
            dparams[self.param_name] += dresids[self.out_name]
dataset/ETHPy150Open OpenMDAO/OpenMDAO/openmdao/components/unit_comp.py/UnitComp.apply_linear/operator `==` -> `<`