初等相似变换将一般实矩阵约化为上H矩阵，包括主函数、双重步QR方法求一般实矩阵全部特征值的函数和约化为上H矩阵的函数。-Elementary similarity transformation will generally be reduced to the real matrix H matrix, including the main function, the double-step method for solving general real matrix QR all eigenvalues ​ ​ of the matrix function about as a function of H.