Abstract: The diagonalization of matrices is an important problem in Matrix Theory. In this paper we summarized* many conditions for diagonalizable matrices using related theories in higher algebra. Then we gave several methods of diagonalizing : diagonal matrix, eigenvalue, eigenvector *: 如果你们论文中只是总结了前人的条件,用summarized。如果在前人基础上有改进,可用generalized。