mod_arpack_type – Legolas v. 2.1.1

Contains a dedicated type for the various settings of the ARPACK solvers. All variables that are used in different solver settings are defined, initialised and set in this module.

Uses

Derived Types

type, public :: arpack_t

General type containing the ARPACK configuration.

Components

Type	Visibility	Attributes		Name
integer,	private		::	mode	mode of the solver
integer,	public		::	ido	reverse communication flag
character(len=1),	private		::	bmat	type of the matrix B ("I" = unit matrix, "G" = general matrix)
integer,	private		::	evpdim	dimension of the eigenvalue problem
character(len=2),	private		::	which	which eigenvalues to calculate
integer,	private		::	nev	number of eigenvalues to calculate
real(kind=dp),	private		::	tolerance	stopping criteria, relative accuracy of Ritz eigenvalues
complex(kind=dp),	public,	allocatable	::	residual(:)	residual vector
integer,	private		::	ncv	indicates how many Arnoldi vectors are generated each iteration
integer,	public		::	iparam(11)	integer array containing mode and parameters
integer,	private		::	lworkl	length of workl array, must be at least 3 * ncv*2 + 5 ncv
integer,	public		::	info	info parameter
integer,	private		::	maxiter	maximum number of iterations

Type-Bound Procedures

procedure, public :: get_bmat
procedure, public :: get_evpdim
procedure, public :: get_which
procedure, public :: get_nev
procedure, public :: get_tolerance
procedure, public :: get_ncv
procedure, public :: get_maxiter
procedure, public :: get_lworkl
procedure, public :: parse_znaupd_info
procedure, public :: parse_zneupd_info
procedure, public :: parse_finished_stats
procedure, public :: destroy
procedure, private :: set_mode
procedure, private :: set_bmat
procedure, private :: set_which
procedure, private :: set_nev
procedure, private :: set_residual
procedure, private :: set_ncv
procedure, private :: set_maxiter

Functions

public function new_arpack_config(evpdim, mode, bmat, solver_settings) result(arpack_config)

Constructor for a new ARPACK configuration based on the dimension of the eigenvalue problem, mode of the solver and type of the B-matrix. Initialises required variables and allocates work arrays to be used when calling the solvers.

Arguments

Type	Intent		Name
integer,	intent(in)	::	evpdim	dimension of the eigenvalue problem
integer,	intent(in)	::	mode	mode for the solver
character(len=1),	intent(in)	::	bmat	type of the matrix B
type(solver_settings_t),	intent(inout)	::	solver_settings

Return Value type(arpack_t)

initialised arpack configuration

private pure function get_bmat(this)

Getter for kind of B-matrix in eigenvalue problem.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value character

private pure function get_evpdim(this)

Getter for dimension of eigenvalue problem.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value integer

private pure function get_which(this)

Getter for which eigenvalues to return.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value character(len=2)

private pure function get_nev(this)

Getter for number of eigenvalues to calculate.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value integer

private pure function get_tolerance(this)

Getter for tolerance (relative accuracy) to indicate eigenvalue convergence.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value real(kind=dp)

private pure function get_ncv(this)

Getter for number of Arnoldi basis vectors that should be calculated.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value integer

private pure function get_maxiter(this)

Getter for maximum number of iterations.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value integer

private pure function get_lworkl(this)

Getter for length of workl array, returns 3 * ncv**2 + 5 * ncv

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

Return Value integer

Subroutines

private subroutine set_mode(this, mode)

Sets the mode for the solver.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
integer,	intent(in)			::	mode	solver mode

private subroutine set_bmat(this, bmat)

Sets the type of B-matrix.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
character,	intent(in)			::	bmat	type of B-matrix

private subroutine set_which(this, which)

Setter for the "which" argument of ARPACK routines.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
character(len=2),	intent(in)			::	which	which kind of eigenvalues to calculate

private subroutine set_nev(this, nev)

Setter for number of eigenvalues to calculate.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
integer,	intent(in)			::	nev	number of eigenvalues to calculate

private subroutine set_residual(this, evpdim)

Setter for the residual vector, allocates and manually initialises the residual (= starting) vector using a uniform distribution on (-1, 1) for both the real and imaginary parts. Relies on the LAPACK routine zlarnv.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
integer,	intent(in)			::	evpdim	dimension of the eigenvalue problem

private subroutine set_ncv(this, ncv)

Setter for ncv, the number of Arnoldi basis vectors to calculate. This should satisfy 1 <= ncv - nev and ncv <= evpdim, with recommended value ncv = 2 * nev (see arpack docs).

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
integer,	intent(in)			::	ncv	value for ncv

private subroutine set_maxiter(this, maxiter)

Sets the maximum number of iterations that ARPACK is allowed to take, defaults to max(100, 10 * k) with k the number of eigenvalues.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance
integer,	intent(in)			::	maxiter	maximum number of iterations

private pure subroutine destroy(this)

Destructor, deallocates variables.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(inout)			::	this	type instance

private subroutine parse_znaupd_info(this, converged)

Parses the info parameter that comes out of ARPACK's znaupd method. If info = 0, everything behaved nicely and the reverse communication subroutines exited properly. If info is any other value something went wrong and we handle it accordingly.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	reference to type object
logical,	intent(out)			::	converged	if .true. the reverse communication routines converged, .false. otherwise

private subroutine parse_zneupd_info(this)

Parses the info parameter that comes out of ARPACK's zneupd method. If info = 0, the eigenvalues extraction routines exited properly, if info is any other value something went wrong and we handle it accordingly.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	reference to type object

private subroutine parse_finished_stats(this)

Parses the statistics that come out of ARPACK when the run is finished. Displays the number of OPX and BX operations and the number of re-orthogonalisation steps that were needed.

Arguments

Type	Intent	Optional	Attributes		Name
class(arpack_t),	intent(in)			::	this	type instance

mod_arpack_type Module

Contents

Derived Types

Functions

Subroutines

Uses

Contents

Derived Types

Functions

Subroutines

Derived Types

type, public :: arpack_t

Components

Type-Bound Procedures

Functions

public function new_arpack_config(evpdim, mode, bmat, solver_settings) result(arpack_config)

Arguments

Return Value type(arpack_t)

private pure function get_bmat(this)

Arguments

Return Value character

private pure function get_evpdim(this)

Arguments

Return Value integer

private pure function get_which(this)

Arguments

Return Value character(len=2)

private pure function get_nev(this)

Arguments

Return Value integer

private pure function get_tolerance(this)

Arguments

Return Value real(kind=dp)

private pure function get_ncv(this)

Arguments

Return Value integer

private pure function get_maxiter(this)

Arguments

Return Value integer

private pure function get_lworkl(this)

Arguments

Return Value integer

Subroutines

private subroutine set_mode(this, mode)

Arguments

private subroutine set_bmat(this, bmat)

Arguments

private subroutine set_which(this, which)

Arguments

private subroutine set_nev(this, nev)

Arguments

private subroutine set_residual(this, evpdim)

Arguments

private subroutine set_ncv(this, ncv)

Arguments

private subroutine set_maxiter(this, maxiter)

Arguments

private pure subroutine destroy(this)

Arguments

private subroutine parse_znaupd_info(this, converged)

Arguments

private subroutine parse_zneupd_info(this)

Arguments

private subroutine parse_finished_stats(this)

Arguments