def VoltageControlledCurrentSource(G, Z0=50):
    """VoltageControlledCurrentSource
    Voltage controlled current source
    @param G float or complex transconductance
    @param Z0 (optional) float or complex reference impedance Z0 (defaults to 50 ohms)
    @return list of list s-parameter matrix of a voltage controlled current source
    @remark
    The four port voltage controlled current source has
    the voltage sense element sensing the voltage difference between the plus terminal
    at port 1 and the minus terminal at port 2.

    The current generated by the amplifier enters port 4 and exits port 3
    """
    return [[1.0, 0.0, 0.0, 0.0], [0.0, 1.0, 0.0, 0.0], [2.0 * G * Z0, -2.0 *
        G * Z0, 1.0, 0.0], [-2.0 * G * Z0, 2.0 * G * Z0, 0.0, 1.0]]
