def _linear_conversion(vector, cc_val):
    """ apply linear conversion to data

    Parameters
    ----------------
    vector : numpy 1D array
        raw data to be converted to physical value
    cc_val : mdfinfo4.info4 conversion block ('CCBlock') dict

    Returns
    -----------
    converted data to physical value
    """
    p1 = cc_val[0]
    p2 = cc_val[1]
    if p2 == 1.0 and p1 in (0.0, -0.0):
        return vector
    else:
        return vector * p2 + p1
