13.3.6 Convert_ELL_to_LAMG Procedure

The Convert_ELL_to_LAMG procedure converts an ELL Matrix object to the LAMG matrix storage format. While converting to the LAMG CSR (compressed storage row) format, the zero entries in the ELL Matrix are removed, which will result in faster operation. This function is only available if CÆSAR has been compiled with LAMG.

Calling syntax:

call Convert (LAMG_Matrix, ELLM, LAMG_Communicator, LAMG_Options, status)

Input variables:

	ELLM		The ELL_Matrix object to be converted.
	LAMG_Communicator		The Communicator object for the LAMG package.
	LAMG_Options		The Options object for the LAMG package.

Output variables:

	LAMG_Matrix		The matrix in LAMG format.
	status		If present, the status variable is set to either 'Memory Error' or 'Success' depending on program execution. If not present, the procedure aborts if unsuccessful when the DEBUG_LEVEL is set high enough.

Internal variables:

	Status variables
	allocate_status		Allocation Status.
	consolidated_status		Consolidated Status.
	LAMG_Status		LAMG status.
	Matrix variables
	NNonzeros_PE		Number of nonzeros on this PE.
	Columns_BNA		Matrix columns bare naked array.
	Values_BNA		Matrix values bare naked array.
	LAMG_BR_Matrix		LAMG block-row format matrix.
	Counter variables
	BR_Location		Location in the block-row matrix.
	ELL_Location		Location in the ELL matrix.
	row		Row loop counter.

The Convert_ELL_to_LAMG code listing contains additional documentation.