myNotes/worksAndStudy/populate_indicators函数.md

    # 1. 计算指标
    def populate_indicators(self, dataframe: pd.DataFrame, metadata: dict) -> pd.DataFrame:
        # 计算 20 周期指数均线
        dataframe['ema20'] = dataframe['close'].ewm(span=20, adjust=False).mean()
        return dataframe

参数：这里的参数

1. self：