gko::solver::multigrid Namespace Reference

The solver multigrid namespace. More...

Enumerations
enum	cycle { v, f, w }
	cycle defines which kind of multigrid cycle can be used. More...
enum	mid_smooth_type { both, post_smoother, pre_smoother, standalone }
	mid_smooth_type gives the options to handle the middle smoother behavior between the two cycles in the same level. More...

Detailed Description

The solver multigrid namespace.

Enumeration Type Documentation

cycle

enum gko::solver::multigrid::cycle

strong

cycle defines which kind of multigrid cycle can be used.

It contains V, W, and F cycle.

• V, W cycle uses the algorithm according to Briggs, Henson, and McCormick: A multigrid tutorial 2nd Edition.
• F cycle uses the algorithm according to Trottenberg, Oosterlee, and Schuller: Multigrid 1st Edition. F cycle first uses the recursive call but second uses the V-cycle call such that F-cycle is between V and W cycle.

mid_smooth_type

enum gko::solver::multigrid::mid_smooth_type

strong

mid_smooth_type gives the options to handle the middle smoother behavior between the two cycles in the same level.

It only affects the behavior when there's no operation between the post smoother of previous cycle and the pre smoother of next cycle. Thus, it only affects W cycle and F cycle.

• both: gives the same behavior as the original algorithm, which use posts smoother from previous cycle and pre smoother from next cycle.
• post_smoother: only uses the post smoother of previous cycle in the mid smoother
• pre_smoother: only uses the pre smoother of next cycle in the mid smoother
• standalone: uses the defined smoother in the mid smoother