解释每条语句作用def cal_linear(iaqi_lo, iaqi_hi, bp_lo, bp_hi, cp): #范围缩放 iaqi = (iaqi_hi - iaqi_lo) * (cp - bp_lo) / (bp_hi - bp_lo) + iaqi_lo return iaqi def cal_pm_iaqi(pm_val): #计算PM2.5的IAQI if 0 <= pm_val < 35: iaqi = cal_linear(0, 50, 0, 35, pm_val) elif 35 <= pm_val < 75: iaqi = cal_linear(50, 100, 35, 75, pm_val) elif 75 <= pm_val < 115: iaqi = cal_linear(100, 150, 75, 115, pm_val) else: pass return iaqi def cal_co_iaqi(co_val): #计算CO的IAQI if 0 <= co_val < 3: iaqi = cal_linear(0, 50, 0, 3, co_val) elif 3 <= co_val < 5: iaqi = cal_linear(50, 100, 2, 4, co_val) else: pass return iaqi def cal_aqi(para_list): #AQI计算 pm_val = para_list[0] co_val = para_list[1] pm_iaqi = cal_pm_iaqi(pm_val) co_iaqi = cal_co_iaqi(co_val) iaqi_list = [] iaqi_list.append(pm_iaqi) iaqi_list.append(co_iaqi) aqi = max(iaqi_list) return aqi def main(): #主函数 print('请输入以下信息，用空格分隔') input_str = input('(1)PM2.5 (2)CO:') str_list = input_str.split(' ') pm_val = float(str_list[0]) co_val = float(str_list[1]) para_list = [] para_list.append(pm_val) para_list.append(co_val) # 调用AQI计算函数 aqi_val = cal_aqi(para_list) print('空气质量指数为：{}'.format(aqi_val)) if name == 'main': main()

这段代码是一个空气质量指数（AQI）计算器的实现。函数`cal_linear()`用于将一个值的范围从一个区间映射到另一个区间，函数`cal_pm_iaqi()`用于计算PM2.5浓度对应的IAQI值，函数`cal_co_iaqi()`用于计算CO浓度对应的IAQI值，函数`cal_aqi()`用于计算AQI值，最终在`main()`函数中将用户输入的PM2.5和CO浓度值传入`cal_aqi()`函数中计算AQI值，并输出结果。