利用矩阵的奇异值分解,建立了子矩阵约束下的矩阵反问题AX=B对称解存在的充分必要条件,并给出通解的表达式。进而,考虑了对任一给定矩阵的最佳逼近问题,得到了最佳逼近解。
Using the singular value decomposition (SVD) of a matrix, this paper establishes the necessary and sufficient conditions for the existence of the symmetric solutions and the expressions for the Inverse problem of a matrix under a submatrix constraint. Moreover, the optimal approximation problem to a given matrix in the solution set is considered, and the optimal approximation solution is obtained.