oft_arpack Module Reference

Detailed Description

Interface to parallel ARPACK for eigenvalue problems.

• IR-Arnoldi (General)
• IR-Lanczos (Symmetric)

Authors

Chris Hansen

Date

June 2012

Data Types
interface	dnaupd
	Interface to pdnaupd from ARPACK. More...
interface	dneupd
	Interface to dneupd from ARPACK. More...
interface	dsaupd
	Interface to pdsaupd from ARPACK. More...
interface	dseupd
	Interface to dseupd from ARPACK. More...
type	oft_iram_eigsolver
	Implicity Restarted Arnoldi Method. More...
type	oft_irlm_eigsolver
	Implicity Restarted Lanczos Method. More...
interface	pdnaupd
	Interface to pdnaupd from ARPACK. More...
interface	pdneupd
	Interface to pdneupd from ARPACK. More...
interface	pdsaupd
	Interface to pdsaupd from ARPACK. More...
interface	pdseupd
	Interface to pdseupd from ARPACK. More...

Functions/Subroutines
subroutine	iram_delete (self)
	Destroy diagonal preconditioner and deallocate all internal storage.
subroutine	iram_eig_apply (self, u, alam)
	Compute the eigenvalue and eigenvector of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Arnoldi Iteration.
subroutine	iram_eig_max (self, u, alam)
	Compute the largest 2 eigenvalues of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Arnoldi Iteration.
subroutine	irlm_delete (self)
	Destroy diagonal preconditioner and deallocate all internal storage.
subroutine	irlm_eig_apply (self, u, alam)
	Compute the eigenvalue and eigenvector of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Lanczos Iteration.
subroutine	irlm_eig_max (self, u, alam)
	Compute the largest 2 eigenvalues of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Lanczos Iteration.

Function/Subroutine Documentation

iram_delete()

subroutine iram_delete ( class(oft_iram_eigsolver), intent(inout)  self )

private

Destroy diagonal preconditioner and deallocate all internal storage.

iram_eig_apply()

subroutine iram_eig_apply ( class(oft_iram_eigsolver), intent(inout)  self, class(oft_vector), intent(inout)  u, real(r8), intent(inout)  alam  )

private

Compute the eigenvalue and eigenvector of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Arnoldi Iteration.

Solver employs the ARPACK non-symmetric driver routine. The location of the eigenvalue is set in the calling class.

Parameters

[in,out]	u	Guess field/Eigenvector
[in,out]	alam	Eigenvalue

iram_eig_max()

subroutine iram_eig_max ( class(oft_iram_eigsolver), intent(inout)  self, class(oft_vector), intent(inout)  u, real(r8), intent(inout)  alam  )

private

Compute the largest 2 eigenvalues of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Arnoldi Iteration.

Solver employs the ARPACK non-symmetric driver routine. Currently the guess field is only used to create work vectors and a random initialization is used for the solver.

Parameters

[in,out]	u	Guess field/Eigenvector
[in,out]	alam	Eigenvalue

irlm_delete()

subroutine irlm_delete ( class(oft_irlm_eigsolver), intent(inout)  self )

private

Destroy diagonal preconditioner and deallocate all internal storage.

irlm_eig_apply()

subroutine irlm_eig_apply ( class(oft_irlm_eigsolver), intent(inout)  self, class(oft_vector), intent(inout)  u, real(r8), intent(inout)  alam  )

private

Compute the eigenvalue and eigenvector of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Lanczos Iteration.

Solver employs the ARPACK symmetric driver routine dsaupd. The location of the eigenvalue is set in the calling class.

Parameters

[in,out]	u	Guess field/Eigenvector
[in,out]	alam	Eigenvalue

irlm_eig_max()

subroutine irlm_eig_max ( class(oft_irlm_eigsolver), intent(inout)  self, class(oft_vector), intent(inout)  u, real(r8), intent(inout)  alam  )

private

Compute the largest 2 eigenvalues of a matrix system (A*x = Lam*M*x) using an Implicitly Restarted Lanczos Iteration.

Solver employs the ARPACK symmetric driver routine. Currently the guess field is only used to create work vectors and a random initialization is used for the solver.

Parameters

[in,out]	u	Guess field/Eigenvector
[in,out]	alam	Eigenvalue