chst01.f3

!>
!> CHST01 tests the reduction of a general matrix A to upper Hessenberg
!> form:  A = Q*H*Q'.  Two test ratios are computed;
!>
!> RESULT(1) = norm( A - Q*H*Q' ) / ( norm(A) * N * EPS )
!> RESULT(2) = norm( I - Q'*Q ) / ( N * EPS )
!>
!> The matrix Q is assumed to be given explicitly as it would be
!> following CGEHRD + CUNGHR.
!>
!> In this version, ILO and IHI are not used, but they could be used
!> to save some work if this is desired.
!> 

N

!>          N is INTEGER
!>          The order of the matrix A.  N >= 0.
!> 

ILO

!>          ILO is INTEGER
!> 

IHI

!>          IHI is INTEGER
!>
!>          A is assumed to be upper triangular in rows and columns
!>          1:ILO-1 and IHI+1:N, so Q differs from the identity only in
!>          rows and columns ILO+1:IHI.
!> 

A

!>          A is COMPLEX array, dimension (LDA,N)
!>          The original n by n matrix A.
!> 

LDA

!>          LDA is INTEGER
!>          The leading dimension of the array A.  LDA >= max(1,N).
!> 

H

!>          H is COMPLEX array, dimension (LDH,N)
!>          The upper Hessenberg matrix H from the reduction A = Q*H*Q'
!>          as computed by CGEHRD.  H is assumed to be zero below the
!>          first subdiagonal.
!> 

LDH

!>          LDH is INTEGER
!>          The leading dimension of the array H.  LDH >= max(1,N).
!> 

Q

!>          Q is COMPLEX array, dimension (LDQ,N)
!>          The orthogonal matrix Q from the reduction A = Q*H*Q' as
!>          computed by CGEHRD + CUNGHR.
!> 

LDQ

!>          LDQ is INTEGER
!>          The leading dimension of the array Q.  LDQ >= max(1,N).
!> 

WORK

!>          WORK is COMPLEX array, dimension (LWORK)
!> 

LWORK

!>          LWORK is INTEGER
!>          The length of the array WORK.  LWORK >= 2*N*N.
!> 

RWORK

!>          RWORK is REAL array, dimension (N)
!> 

RESULT

!>          RESULT is REAL array, dimension (2)
!>          RESULT(1) = norm( A - Q*H*Q' ) / ( norm(A) * N * EPS )
!>          RESULT(2) = norm( I - Q'*Q ) / ( N * EPS )
!> 

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