Changing the for loop to a matrix operation when calculating the RSI

_compute_indicator is the function which the RSI is calculated with:

    def _compute_indicator(data_: pd.Series, period: int):
        clean_data = data_.dropna()
        delta = clean_data.diff()
        delta_up = delta.clip(lower=0)
        delta_down = delta.clip(upper=0).abs()
        avg_gain = pd.Series(
            np.full(len(delta_up), np.nan), index=delta_up.index.copy(), name=data_.name
        )
        avg_loss = pd.Series(
            np.full(len(delta_down), np.nan),
            index=delta_down.index.copy(),
            name=data_.name,
        )
        avg_gain[period] = delta_up[: period + 1].mean()
        avg_loss[period] = delta_down[: period + 1].mean()
        for i in range(period + 1, avg_gain.shape[0]):
            avg_gain.iloc[i] = (
                avg_gain.iloc[i - 1] * (period - 1) + delta_up.iloc[i]
            ) / period
            avg_loss.iloc[i] = (
                avg_loss.iloc[i - 1] * (period - 1) + delta_down.iloc[i]
            ) / period
        rs = avg_gain / avg_loss
        rsi_calc = 100 - (100 / (1 + rs))
        return rsi_calc

This is the Code where the function is implemented in:

    if isinstance(data, pd.DataFrame):
        indicator = data.apply(_compute_indicator, period=periods)
        indicator = indicator.reindex(data.index)

    else:
        indicator = _compute_indicator(data, periods)
        indicator = indicator.reindex(data.index)

    return indicator

The Code is checking in an If-Else Statement if it is an pd.Dataframe or a Series-

Question: How to change the for loop to something quicker? Maybe a Matrix operation?

for i in range(period + 1, avg_gain.shape[0]):
            avg_gain.iloc[i] = (
                avg_gain.iloc[i - 1] * (period - 1) + delta_up.iloc[i]
            ) / period
            avg_loss.iloc[i] = (
                avg_loss.iloc[i - 1] * (period - 1) + delta_down.iloc[i]
            ) / period

This is the part which is super slow. But I have no Idea how to make it quicker