Matrix Overlap Type

Matrix overlap type = {standard | symmetric}

Description / Usage

This card selects the kind of matrix overlap that occurs (for parallel computations). Valid options are:

standard

The local processor considers only its own estimate for any unknown; results from adjacent processors are ignored. This is the default.

symmetric

The local processor adds its own estimate together with estimates from adjacent processors, retaining symmetry of preconditioners if a symmetric technique is being employed.

If the Matrix ovelap type card is omitted, the default is standard.

Examples

Following is a sample card:

Matrix overlap type= symmetric

Technical Discussion

This optional card determines how overlapping subdomain solver results are combined when different processors derive different estimates for the same solution unknown.

This overlap option is moot for serial problems whose data decomposition is trivial.