判断半正定矩阵与正定矩阵间的一种新的准则，gky方法是判定系统是否稳定的一种很有效的方法，里面有源代码和相应文档-Judge half positive definite matrix and the positive definite matrix, a new criterion between gky method is to determine whether the system stability of a kind of very effective method, there are source code and documentation accordingly