petsc-3.4.5 2014-06-29

PCGASMSetTotalSubdomains

Sets the total number of subdomains to use in the generalized additive Schwarz preconditioner. The number of subdomains is cumulative across all processors in pc's communicator. Either all or no processors in the PC communicator must call this routine with the same N. The subdomains will be created automatically during PCSetUp().

Synopsis

#include "petscpc.h" 
PetscErrorCode  PCGASMSetTotalSubdomains(PC pc,PetscInt N, PetscBool create_local)

Collective on PC

Input Parameters

	pc	- the preconditioner context
	N	- the total number of subdomains cumulative across all processors
	create_local	- whether the subdomains to be created are to be local

Options Database Key

To set the total number of subdomains and let PCGASM autocreate them, rather than specify the index sets, use the following options

	-pc_gasm_total_subdomains <n>	- sets the total number of subdomains to be autocreated by PCGASM
	-pc_gasm_subdomains_create_local <true\|false>	- whether autocreated subdomains should be local or not (default is true)

By default the GASM preconditioner uses 1 subdomain per processor.

Use PCGASMSetSubdomains() to set subdomains explicitly or to set different numbers of subdomains per processor.

Keywords