运用MATLAB求取结构的特征值以及相对应向量，其中小曲了刚度矩阵和质量矩阵中对角线为零的选项，消除了矩阵的奇异性-Use MATLAB to strike the structure and the corresponding eigenvalues 瘠攀挀琀漀爀, which ditty stiffness and mass matrices in the diagonal zero option, eliminating the singularity of the matrix