The Centrosymmetric Matrices of Constrained Inverse Eigenproblem and Optimal Approximation Problem

Algorithm 1

The solution of (7).

	Step 1. Input ;
	Step 2. Decompose as equation (10);
	Step 3. Calculate the singular value decomposition as equations (13) and (14), verify that equation (24) is true and A can be expressed as equation (25);
	Step 4. Decompose as equation (35);
	Step 5. Decompose as equations (36), (37), respectively;
	Step 6. Calculate as equations (50) and (52), respectively;
	Step 7. Calculate by Theorem 2.