fitness function for rsi using genetic algorithms

问题

This code is implementing a fitness function for rsi indicators using genetic algorithms but i have no idea what are the output for every function

def strategy_return(trading_signal, asset_return):
    strat_ret = np.array(trading_signal[0:-1]) * np.array(asset_return[1::])
    strat_ret = np.insert(strat_ret, 0, np.nan)
    return strat_ret

def _cumulative_return(ret):
    cum_ret_list = [ret[0]]
    n = ret.shape[0]
    for i in range(1, n):
        cum_ret = (1 + ret[i]) * (1 + cum_ret_list[-1]) - 1
        cum_ret_list.append(cum_ret)
    cum_ret_list.insert(0, np.nan)
    return cum_ret_list

def fit_evaluation(strategy_return):
    strat_cum_ret = _cumulative_return(strat_ret[1::])
    return strat_cum_ret

来源：https://stackoverflow.com/questions/65580865/fitness-function-for-rsi-using-genetic-algorithms