def sigmoid2 (x, parameters):
    """Sigmoid 2 function
    POI = K / (C + (A*x**B))
    
    Parameters
    ----------
    x: float or array of floats or array of floats
        variable
    parameters: dict
        dictionary containing 'sigmoid2_K','sigmoid2_C','sigmoid2_A',
        and 'sigmoid2_B'
        
    Returns
    -------
    float or array of floats:
        function  result
    """
    K = parameters['sigmoid2_K']
    C = parameters['sigmoid2_C']
    A = parameters['sigmoid2_A']
    B = parameters['sigmoid2_B']
    return K / (C + (A * x**B))