def flow_rect_weir(Height, Width):
    """Return the flow of a rectangular weir."""
    #Checking input validity
    ut.check_range([Height, ">0", "Height"], [Width, ">0", "Width"])
    return ((2/3) * con.VC_ORIFICE_RATIO
            * (np.sqrt(2*gravity.magnitude) * Height**(3/2))
            * Width)