dget51.f3

!>
!>      DGET51  generally checks a decomposition of the form
!>
!>              A = U B V'
!>
!>      where ' means transpose and U and V are orthogonal.
!>
!>      Specifically, if ITYPE=1
!>
!>              RESULT = | A - U B V' | / ( |A| n ulp )
!>
!>      If ITYPE=2, then:
!>
!>              RESULT = | A - B | / ( |A| n ulp )
!>
!>      If ITYPE=3, then:
!>
!>              RESULT = | I - UU' | / ( n ulp )
!> 

ITYPE

!>          ITYPE is INTEGER
!>          Specifies the type of tests to be performed.
!>          =1: RESULT = | A - U B V' | / ( |A| n ulp )
!>          =2: RESULT = | A - B | / ( |A| n ulp )
!>          =3: RESULT = | I - UU' | / ( n ulp )
!> 

N

!>          N is INTEGER
!>          The size of the matrix.  If it is zero, DGET51 does nothing.
!>          It must be at least zero.
!> 

A

!>          A is DOUBLE PRECISION array, dimension (LDA, N)
!>          The original (unfactored) matrix.
!> 

LDA

!>          LDA is INTEGER
!>          The leading dimension of A.  It must be at least 1
!>          and at least N.
!> 

B

!>          B is DOUBLE PRECISION array, dimension (LDB, N)
!>          The factored matrix.
!> 

LDB

!>          LDB is INTEGER
!>          The leading dimension of B.  It must be at least 1
!>          and at least N.
!> 

U

!>          U is DOUBLE PRECISION array, dimension (LDU, N)
!>          The orthogonal matrix on the left-hand side in the
!>          decomposition.
!>          Not referenced if ITYPE=2
!> 

LDU

!>          LDU is INTEGER
!>          The leading dimension of U.  LDU must be at least N and
!>          at least 1.
!> 

V

!>          V is DOUBLE PRECISION array, dimension (LDV, N)
!>          The orthogonal matrix on the left-hand side in the
!>          decomposition.
!>          Not referenced if ITYPE=2
!> 

LDV

!>          LDV is INTEGER
!>          The leading dimension of V.  LDV must be at least N and
!>          at least 1.
!> 

WORK

!>          WORK is DOUBLE PRECISION array, dimension (2*N**2)
!> 

RESULT

!>          RESULT is DOUBLE PRECISION
!>          The values computed by the test specified by ITYPE.  The
!>          value is currently limited to 1/ulp, to avoid overflow.
!>          Errors are flagged by RESULT=10/ulp.
!> 

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