""" Optuna 优化引擎。 统一接口:optimizer.optimize(strategy_class, space, price_df, factor_df) → OptimizationResult """ import copy import time import numpy as np import optuna import pandas as pd from backtest.base import BaseStrategy from backtest.report import BacktestReport from backtest.vectorbt.engine import VectorBTEngine from optimizer.objectives import Objective from optimizer.result import OptimizationResult, WalkForwardResult from optimizer.space import SearchSpace # 抑制 Optuna 日志 optuna.logging.set_verbosity(optuna.logging.WARNING) class OptunaEngine: """ Optuna 优化引擎。 """ def __init__(self, bt_engine: VectorBTEngine | None = None): self.bt_engine = bt_engine or VectorBTEngine() def optimize( self, strategy_class: type[BaseStrategy], search_space: SearchSpace, price_df: pd.DataFrame, factor_df: pd.DataFrame | None = None, metric: str = "sharpe", n_trials: int = 100, direction: str = "maximize", sampler: optuna.samplers.BaseSampler | None = None, ) -> OptimizationResult: """ 参数寻优。 参数: strategy_class: 策略类 search_space: 搜索空间 price_df: 价格数据 factor_df: 因子数据 metric: 优化目标 n_trials: 试验次数 direction: 'maximize' | 'minimize' sampler: Optuna 采样器,默认 TPESampler """ if sampler is None: sampler = optuna.samplers.TPESampler(seed=42) study = optuna.create_study( direction=direction, sampler=sampler, ) objective = Objective( strategy_class=strategy_class, search_space=search_space, price_df=price_df, factor_df=factor_df, bt_engine=self.bt_engine, metric=metric, ) t0 = time.time() study.optimize(objective, n_trials=n_trials, show_progress_bar=True) elapsed = time.time() - t0 # 用最优参数跑一次完整回测 best_params = study.best_params try: best_strategy = strategy_class(**best_params) except TypeError: valid = {k: v for k, v in best_params.items() if k in strategy_class.__init__.__code__.co_varnames} best_strategy = strategy_class(**valid) best_report = self.bt_engine.run( best_strategy, price_df, price_df if factor_df is None else factor_df, ) # 参数重要性 try: importance = optuna.importance.get_param_importances(study) except Exception: importance = {} # 试验记录 trials_df = study.trials_dataframe() return OptimizationResult( best_params=study.best_params, best_value=study.best_value, metric=metric, best_report=best_report, trials_df=trials_df, param_importance=importance, ) def optimize_walk_forward( self, strategy_class: type[BaseStrategy], search_space: SearchSpace, price_df: pd.DataFrame, factor_df: pd.DataFrame | None = None, metric: str = "sharpe", n_trials: int = 100, train_window: int = 252 * 3, test_window: int = 252, ) -> WalkForwardResult: """ 滚动窗口优化(Walk-Forward Analysis)。 每一步:train_window 训练 → test_window 验证 → 滑动。 """ if factor_df is None: factor_df = price_df n_total = len(price_df) windows = [] test_equities = [] param_history = [] start = 0 while start + train_window + test_window <= n_total: train_slice = slice(start, start + train_window) test_slice = slice(start + train_window, start + train_window + test_window) train_price = price_df.iloc[train_slice] train_factor = factor_df.iloc[train_slice] test_price = price_df.iloc[test_slice] test_factor = factor_df.iloc[test_slice] # 训练集上优化 opt_result = self.optimize( strategy_class=strategy_class, search_space=search_space, price_df=train_price, factor_df=train_factor, metric=metric, n_trials=n_trials, ) # 测试集上验证 try: test_strategy = strategy_class(**opt_result.best_params) except TypeError: valid = {k: v for k, v in opt_result.best_params.items() if k in strategy_class.__init__.__code__.co_varnames} test_strategy = strategy_class(**valid) test_report = self.bt_engine.run(test_strategy, test_price, test_factor) if len(test_report.equity_curve) > 0: test_equities.append(test_report.equity_curve) train_idx = train_price.index test_idx = test_price.index windows.append({ "train_start": train_idx[0] if len(train_idx) > 0 else "", "train_end": train_idx[-1] if len(train_idx) > 0 else "", "test_start": test_idx[0] if len(test_idx) > 0 else "", "test_end": test_idx[-1] if len(test_idx) > 0 else "", "best_params": opt_result.best_params, "best_value": opt_result.best_value, "test_return": test_report.total_return, "test_sharpe": test_report.sharpe_ratio, "test_mdd": test_report.max_drawdown, }) param_history.append(opt_result.best_params) start += test_window # 合并测试期权益曲线 consolidated = _merge_test_periods(test_equities, self.bt_engine.initial_capital) # 参数稳定性 param_df = pd.DataFrame(param_history) if param_history else pd.DataFrame() if not param_df.empty: param_df.index.name = "window" return WalkForwardResult( windows=windows, consolidated_report=consolidated, param_stability=param_df, ) def _merge_test_periods( equity_list: list[pd.Series], initial_capital: float = 100_000, ) -> BacktestReport | None: """拼接各窗口测试期权益曲线为一个连续序列。""" if not equity_list: return None merged = pd.concat(equity_list) merged = merged.sort_index() merged = merged[~merged.index.duplicated()] # 确保 DatetimeIndex if not isinstance(merged.index, pd.DatetimeIndex): merged.index = pd.to_datetime(merged.index, format="%Y%m%d") dd = merged / merged.cummax() - 1 daily_ret = merged.pct_change().dropna() years = max(len(daily_ret) / 252, 0.02) total_ret = (merged.iloc[-1] / merged.iloc[0] - 1) * 100 cagr = ((total_ret / 100 + 1) ** (1 / years) - 1) * 100 mdd = dd.min() * 100 std_ret = daily_ret.std() * np.sqrt(252) sharpe = (daily_ret.mean() * 252) / std_ret if std_ret > 0 else 0 calmar = cagr / abs(mdd) if abs(mdd) > 0 else 0 try: monthly = merged.resample("ME").last().pct_change() except Exception: monthly = pd.Series(dtype=float) return BacktestReport( total_return=round(total_ret, 2), cagr=round(cagr, 2), max_drawdown=round(mdd, 2), sharpe_ratio=round(sharpe, 2), calmar_ratio=round(calmar, 2), annual_volatility=round(std_ret * 100 if std_ret != 0 else 0, 2), equity_curve=merged, drawdown_curve=dd, monthly_returns=monthly, )