TESTING/EIG/zsgt01.f(3) Library Functions Manual TESTING/EIG/zsgt01.f(3)

TESTING/EIG/zsgt01.f


subroutine zsgt01 (itype, uplo, n, m, a, lda, b, ldb, z, ldz, d, work, rwork, result)
ZSGT01

ZSGT01

Purpose:

!>
!> CDGT01 checks a decomposition of the form
!>
!>    A Z   =  B Z D or
!>    A B Z =  Z D or
!>    B A Z =  Z D
!>
!> where A is a Hermitian matrix, B is Hermitian positive definite,
!> Z is unitary, and D is diagonal.
!>
!> One of the following test ratios is computed:
!>
!> ITYPE = 1:  RESULT(1) = | A Z - B Z D | / ( |A| |Z| n ulp )
!>
!> ITYPE = 2:  RESULT(1) = | A B Z - Z D | / ( |A| |Z| n ulp )
!>
!> ITYPE = 3:  RESULT(1) = | B A Z - Z D | / ( |A| |Z| n ulp )
!> 

Parameters

ITYPE
!>          ITYPE is INTEGER
!>          The form of the Hermitian generalized eigenproblem.
!>          = 1:  A*z = (lambda)*B*z
!>          = 2:  A*B*z = (lambda)*z
!>          = 3:  B*A*z = (lambda)*z
!> 

UPLO

!>          UPLO is CHARACTER*1
!>          Specifies whether the upper or lower triangular part of the
!>          Hermitian matrices A and B is stored.
!>          = 'U':  Upper triangular
!>          = 'L':  Lower triangular
!> 

N

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

M

!>          M is INTEGER
!>          The number of eigenvalues found.  M >= 0.
!> 

A

!>          A is COMPLEX*16 array, dimension (LDA, N)
!>          The original Hermitian matrix A.
!> 

LDA

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

B

!>          B is COMPLEX*16 array, dimension (LDB, N)
!>          The original Hermitian positive definite matrix B.
!> 

LDB

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

Z

!>          Z is COMPLEX*16 array, dimension (LDZ, M)
!>          The computed eigenvectors of the generalized eigenproblem.
!> 

LDZ

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

D

!>          D is DOUBLE PRECISION array, dimension (M)
!>          The computed eigenvalues of the generalized eigenproblem.
!> 

WORK

!>          WORK is COMPLEX*16 array, dimension (N*N)
!> 

RWORK

!>          RWORK is DOUBLE PRECISION array, dimension (N)
!> 

RESULT

!>          RESULT is DOUBLE PRECISION array, dimension (1)
!>          The test ratio as described above.
!> 

Author

Univ. of Tennessee

Univ. of California Berkeley

Univ. of Colorado Denver

NAG Ltd.

Definition at line 150 of file zsgt01.f.

Generated automatically by Doxygen for LAPACK from the source code.

Version 3.12.0 LAPACK