la_lapack::hseqr Interface Reference

HSEQR: computes the eigenvalues of a Hessenberg matrix H and, optionally, the matrices T and Z from the Schur decomposition H = Z T Z**H, where T is an upper triangular matrix (the Schur form), and Z is the unitary matrix of Schur vectors. Optionally Z may be postmultiplied into an input unitary matrix Q so that this routine can give the Schur factorization of a matrix A which has been reduced to the Hessenberg form H by the unitary matrix Q: A = Q*H*Q**H = (QZ)*T*(QZ)**H. More...

Public Member Functions
pure subroutine	chseqr (job, compz, n, ilo, ihi, h, ldh, w, z, ldz, work, lwork, info)
	la_chseqr
subroutine	dhseqr (job, compz, n, ilo, ihi, h, ldh, wr, wi, z, ldz, work, lwork, info)
	la_dhseqr
	la_qhseqr
subroutine	shseqr (job, compz, n, ilo, ihi, h, ldh, wr, wi, z, ldz, work, lwork, info)
	la_shseqr
	la_whseqr
pure subroutine	zhseqr (job, compz, n, ilo, ihi, h, ldh, w, z, ldz, work, lwork, info)
	la_zhseqr

Detailed Description

HSEQR: computes the eigenvalues of a Hessenberg matrix H and, optionally, the matrices T and Z from the Schur decomposition H = Z T Z**H, where T is an upper triangular matrix (the Schur form), and Z is the unitary matrix of Schur vectors. Optionally Z may be postmultiplied into an input unitary matrix Q so that this routine can give the Schur factorization of a matrix A which has been reduced to the Hessenberg form H by the unitary matrix Q: A = Q*H*Q**H = (QZ)*T*(QZ)**H.

Member Function/Subroutine Documentation

chseqr()

pure subroutine la_lapack::hseqr::chseqr	(	character, intent(in)	job,
		character, intent(in)	compz,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	ilo,
		integer(ilp), intent(in)	ihi,
		complex(sp), dimension(ldh,*), intent(inout)	h,
		integer(ilp), intent(in)	ldh,
		complex(sp), dimension(*), intent(out)	w,
		complex(sp), dimension(ldz,*), intent(inout)	z,
		integer(ilp), intent(in)	ldz,
		complex(sp), dimension(*), intent(out)	work,
		integer(ilp), intent(in)	lwork,
		integer(ilp), intent(out)	info
	)

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dhseqr()

subroutine la_lapack::hseqr::dhseqr	(	character, intent(in)	job,
		character, intent(in)	compz,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	ilo,
		integer(ilp), intent(in)	ihi,
		real(dp), dimension(ldh,*), intent(inout)	h,
		integer(ilp), intent(in)	ldh,
		real(dp), dimension(*), intent(out)	wr,
		real(dp), dimension(*), intent(out)	wi,
		real(dp), dimension(ldz,*), intent(inout)	z,
		integer(ilp), intent(in)	ldz,
		real(dp), dimension(*), intent(out)	work,
		integer(ilp), intent(in)	lwork,
		integer(ilp), intent(out)	info
	)

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la_chseqr()

la_lapack::hseqr::la_chseqr

la_dhseqr()

la_lapack::hseqr::la_dhseqr

la_qhseqr()

la_lapack::hseqr::la_qhseqr

la_shseqr()

la_lapack::hseqr::la_shseqr

la_whseqr()

la_lapack::hseqr::la_whseqr

la_zhseqr()

la_lapack::hseqr::la_zhseqr

shseqr()

subroutine la_lapack::hseqr::shseqr	(	character, intent(in)	job,
		character, intent(in)	compz,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	ilo,
		integer(ilp), intent(in)	ihi,
		real(sp), dimension(ldh,*), intent(inout)	h,
		integer(ilp), intent(in)	ldh,
		real(sp), dimension(*), intent(out)	wr,
		real(sp), dimension(*), intent(out)	wi,
		real(sp), dimension(ldz,*), intent(inout)	z,
		integer(ilp), intent(in)	ldz,
		real(sp), dimension(*), intent(out)	work,
		integer(ilp), intent(in)	lwork,
		integer(ilp), intent(out)	info
	)

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zhseqr()

pure subroutine la_lapack::hseqr::zhseqr	(	character, intent(in)	job,
		character, intent(in)	compz,
		integer(ilp), intent(in)	n,
		integer(ilp), intent(in)	ilo,
		integer(ilp), intent(in)	ihi,
		complex(dp), dimension(ldh,*), intent(inout)	h,
		integer(ilp), intent(in)	ldh,
		complex(dp), dimension(*), intent(out)	w,
		complex(dp), dimension(ldz,*), intent(inout)	z,
		integer(ilp), intent(in)	ldz,
		complex(dp), dimension(*), intent(out)	work,
		integer(ilp), intent(in)	lwork,
		integer(ilp), intent(out)	info
	)

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

• la_lapack.f90