la_schur::schur_space Interface Reference

Compute the required workspace size for Schur decomposition. More...

Public Member Functions
subroutine	get_schur_s_workspace (a, lwork, err)
subroutine	get_schur_d_workspace (a, lwork, err)
	Input matrix a[m,m].
subroutine	get_schur_q_workspace (a, lwork, err)
	Input matrix a[m,m].
subroutine	get_schur_c_workspace (a, lwork, err)
	Input matrix a[m,m].
subroutine	get_schur_z_workspace (a, lwork, err)
	Input matrix a[m,m].
subroutine	get_schur_w_workspace (a, lwork, err)

Detailed Description

Compute the required workspace size for Schur decomposition.

This subroutine determines the minimum workspace size required for the Schur decomposition of a matrix. The required size depends on the matrix dimensions and type (real or complex).

Parameters

[in]	A	The input matrix of size $[m, m]$.
[out]	lwork	The minimum workspace size required for the decomposition.
[out]	err	(Optional) State return flag. If provided, it will return an error status in case of failure.

Note

This routine is useful for pre-allocating workspace when performing multiple decompositions on matrices of the same size, minimizing dynamic memory allocation overhead.

Member Function/Subroutine Documentation

get_schur_c_workspace()

subroutine la_schur::schur_space::get_schur_c_workspace	(	complex(sp), dimension(:,:), intent(in), target	a,
		integer(ilp), intent(out)	lwork,
		type(la_state), intent(out), optional	err )

Input matrix a[m,m].

Schur form of A: upper-triangular or quasi-upper-triangular matrix T Unitary/orthonormal transformation matrix Z Output eigenvalues that appear on the diagonal of T [optional] Provide pre-allocated workspace, size to be checked with schur_space [optional] Can A data be overwritten and destroyed? [optional] State return flag. On error if not requested, the code will stop Compute Schur decomposition with complex eigenvalues

Parameters

[in]	a	Input matrix a[m,m]
[out]	lwork	Minimum workspace size for the decomposition operation
[out]	err	State return flag. Returns an error if the query failed

get_schur_d_workspace()

subroutine la_schur::schur_space::get_schur_d_workspace	(	real(dp), dimension(:,:), intent(in), target	a,
		integer(ilp), intent(out)	lwork,
		type(la_state), intent(out), optional	err )

Input matrix a[m,m].

Schur form of A: upper-triangular or quasi-upper-triangular matrix T Unitary/orthonormal transformation matrix Z Output eigenvalues that appear on the diagonal of T [optional] Provide pre-allocated workspace, size to be checked with schur_space [optional] Can A data be overwritten and destroyed? [optional] State return flag. On error if not requested, the code will stop Compute Schur decomposition with complex eigenvalues

Parameters

[in]	a	Input matrix a[m,m]
[out]	lwork	Minimum workspace size for the decomposition operation
[out]	err	State return flag. Returns an error if the query failed

get_schur_q_workspace()

subroutine la_schur::schur_space::get_schur_q_workspace	(	real(qp), dimension(:,:), intent(in), target	a,
		integer(ilp), intent(out)	lwork,
		type(la_state), intent(out), optional	err )

Input matrix a[m,m].

Schur form of A: upper-triangular or quasi-upper-triangular matrix T Unitary/orthonormal transformation matrix Z Output eigenvalues that appear on the diagonal of T [optional] Provide pre-allocated workspace, size to be checked with schur_space [optional] Can A data be overwritten and destroyed? [optional] State return flag. On error if not requested, the code will stop Compute Schur decomposition with complex eigenvalues

Parameters

[in]	a	Input matrix a[m,m]
[out]	lwork	Minimum workspace size for the decomposition operation
[out]	err	State return flag. Returns an error if the query failed

get_schur_s_workspace()

subroutine la_schur::schur_space::get_schur_s_workspace	(	real(sp), dimension(:,:), intent(in), target	a,
		integer(ilp), intent(out)	lwork,
		type(la_state), intent(out), optional	err )

Parameters

[in]	a	Input matrix a[m,m]
[out]	lwork	Minimum workspace size for the decomposition operation
[out]	err	State return flag. Returns an error if the query failed

get_schur_w_workspace()

subroutine la_schur::schur_space::get_schur_w_workspace	(	complex(qp), dimension(:,:), intent(in), target	a,
		integer(ilp), intent(out)	lwork,
		type(la_state), intent(out), optional	err )

Parameters

[in]	a	Input matrix a[m,m]
[out]	lwork	Minimum workspace size for the decomposition operation
[out]	err	State return flag. Returns an error if the query failed

get_schur_z_workspace()

subroutine la_schur::schur_space::get_schur_z_workspace	(	complex(dp), dimension(:,:), intent(in), target	a,
		integer(ilp), intent(out)	lwork,
		type(la_state), intent(out), optional	err )

Input matrix a[m,m].

Schur form of A: upper-triangular or quasi-upper-triangular matrix T Unitary/orthonormal transformation matrix Z Output eigenvalues that appear on the diagonal of T [optional] Provide pre-allocated workspace, size to be checked with schur_space [optional] Can A data be overwritten and destroyed? [optional] State return flag. On error if not requested, the code will stop Compute Schur decomposition with complex eigenvalues

Parameters

[in]	a	Input matrix a[m,m]
[out]	lwork	Minimum workspace size for the decomposition operation
[out]	err	State return flag. Returns an error if the query failed

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The documentation for this interface was generated from the following file:

• la_schur.f90