Calculates RMS of rates from fitted_rates before and after correction

    Parameters
    ----------
    rates: numpy array of rates of all PMT combinations
    corrected_rates: numpy array of corrected rates for all PMT combinations

    Returns
    -------
    rms_rates: RMS of rates from fitted_rates
    rms_corrected_rates: RMS of corrected_ratesrates from fitted_rates

def calculate_rms_rates(rates, fitted_rates, corrected_rates):
    """Calculates RMS of rates from fitted_rates before and after correction

    Parameters
    ----------
    rates: numpy array of rates of all PMT combinations
    corrected_rates: numpy array of corrected rates for all PMT combinations

    Returns
    -------
    rms_rates: RMS of rates from fitted_rates
    rms_corrected_rates: RMS of corrected_ratesrates from fitted_rates
    """
    rms_rates = np.sqrt(np.mean((rates - fitted_rates)**2))
    rms_corrected_rates = np.sqrt(np.mean((corrected_rates - fitted_rates)**2))
    return rms_rates, rms_corrected_rates