多元线性的拟合实现。-Multiple linear fitting realization47

AQI是空气质量指数，根据SO2、NO2、CO、O3、PM10、PM2.5六种污染物浓度计算AQI值，判断空气质量的好坏

将改进的粒子群算法和GA与SVM相结合，通过参数寻优构建新模型完成对空气质量指数的预测(The improved particle swarm optimization and genetic algorithm are combined with SVM. The prediction of air quality index (AQI) is completed by constructing a new model by parameter optimization.)