说明：  网上的Kalman滤波数据融合示例，此处的特点是添加了详细的注释，并且为了更容易理解和顾名思义，对部份变量和函数名作了修改，使得非常易懂。
(An example of Kalman filtering data fusion on the Internet! Detailed annotations are added and some variables and function names are modified to make them easy to understand.)