GridSearchCV用于设置PCA的维度，解决逻辑回归预测时，PCA维度降维问题。-The PCA does an unsupervised dimensionality reduction, while the logistic regression does the prediction. We use a GridSearchCV to set the dimensionality of the PCA

机器学习多因子策略，SVR ，GridSearchCV ，learning_curve，LinearRegression，RandomForestRegressor(SVR ,GridSearchCV ,learning_curve,LinearRegression,RandomForestRegressor)