Table 2 Bounds of nonzero real eigenvalues of the preconditioned matrix \(\pmb{\mathcal{P}_{SS}^{-1}\mathcal{A}}\) for Example 3.2
From: Eigenvalue bounds of the shift-splitting preconditioned singular nonsymmetric saddle-point matrices
( α , β ) | The estimated bound | The exact bound |
|---|---|---|
(0.0077, 0.0072) | [1.1108e−3, 0.9995] | [0.1356, 0.9990] |
(0.0307, 0.0071) | [1.1108e−3, 0.9981] | [0.1361, 0.9960] |
(0.0538, 0.0071) | [1.1108e−3, 0.9966] | [0.1365, 0.9930] |
(0.0768, 0.0071) | [1.1108e−3, 0.9952] | [0.1370, 0.9900] |