说明：  一个对数据处理的Matlab函数，统计数据的概率分布并画出概率密度曲线，已经验证，将该函数安装在函数工具箱内即可调用。
(A data processing of Matlab function, the probability distribution of the statistical data and draw the probability density curve, have tested, the function will be installed in the tool can function call. )