def METHOD_NAME(ratio_scale, sum_constant, in1, in2, out):
    """ apply ratio scale to flux values
    Parameters
    ----------
    ratio_scale : float
    sum_constant : bool
        if Ture, then the sum of the new flux will be identical to the old flux
    in1 : float
    in2 : float
    out : array
    """
    if in1 == 0. and in2 == 0.:
        out[0] = 0.
        out[1] = 0.
        return
    if sum_constant:
        orig_ratio = in1 / in2
        orig_sum = in1 + in2
        new = orig_sum / (1. + ratio_scale * orig_ratio)
        out[0] = ratio_scale * orig_ratio * new
        out[1] = new
    else:
        out[0] = ratio_scale * in1
        out[1] = in2