Table 4 Number of iterations and solution time in seconds of \(\pmb{\operatorname{PGMRES}(l)}\) iteration method with preconditioner \(\pmb{\mathcal{P}_{1}}\) and the ordinary \(\pmb{\operatorname{GMRES}(l)}\) iteration method, where \(\pmb{\alpha=\{1, 2\}}\)
From: On block diagonal-Schur complements of the block strictly doubly diagonally dominant matrices
l | 30 | 40 | 50 | 60 | 70 | 80 | 90 | |
|---|---|---|---|---|---|---|---|---|
PGMRES(l) | CPU | 0.0106 | 0.0015 | 0.0024 | 0.0018 | 0.0014 | 0.0024 | 0.0015 |
IT | 4 | 4 | 4 | 4 | 4 | 4 | 4 | |
GMRES(l) | CPU | 0.0046 | 0.0054 | 0.0042 | 0.0018 | 0.0042 | 0.0156 | 0.0048 |
IT | 23 | 23 | 23 | 23 | 23 | 23 | 23 | |