LAPACK 3.11.0
LAPACK: Linear Algebra PACKage
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◆ dget54()

subroutine dget54 ( integer  n,
double precision, dimension( lda, * )  a,
integer  lda,
double precision, dimension( ldb, * )  b,
integer  ldb,
double precision, dimension( lds, * )  s,
integer  lds,
double precision, dimension( ldt, * )  t,
integer  ldt,
double precision, dimension( ldu, * )  u,
integer  ldu,
double precision, dimension( ldv, * )  v,
integer  ldv,
double precision, dimension( * )  work,
double precision  result 
)

DGET54

Purpose:
 DGET54 checks a generalized decomposition of the form

          A = U*S*V'  and B = U*T* V'

 where ' means transpose and U and V are orthogonal.

 Specifically,

  RESULT = ||( A - U*S*V', B - U*T*V' )|| / (||( A, B )||*n*ulp )
Parameters
[in]N
          N is INTEGER
          The size of the matrix.  If it is zero, DGET54 does nothing.
          It must be at least zero.
[in]A
          A is DOUBLE PRECISION array, dimension (LDA, N)
          The original (unfactored) matrix A.
[in]LDA
          LDA is INTEGER
          The leading dimension of A.  It must be at least 1
          and at least N.
[in]B
          B is DOUBLE PRECISION array, dimension (LDB, N)
          The original (unfactored) matrix B.
[in]LDB
          LDB is INTEGER
          The leading dimension of B.  It must be at least 1
          and at least N.
[in]S
          S is DOUBLE PRECISION array, dimension (LDS, N)
          The factored matrix S.
[in]LDS
          LDS is INTEGER
          The leading dimension of S.  It must be at least 1
          and at least N.
[in]T
          T is DOUBLE PRECISION array, dimension (LDT, N)
          The factored matrix T.
[in]LDT
          LDT is INTEGER
          The leading dimension of T.  It must be at least 1
          and at least N.
[in]U
          U is DOUBLE PRECISION array, dimension (LDU, N)
          The orthogonal matrix on the left-hand side in the
          decomposition.
[in]LDU
          LDU is INTEGER
          The leading dimension of U.  LDU must be at least N and
          at least 1.
[in]V
          V is DOUBLE PRECISION array, dimension (LDV, N)
          The orthogonal matrix on the left-hand side in the
          decomposition.
[in]LDV
          LDV is INTEGER
          The leading dimension of V.  LDV must be at least N and
          at least 1.
[out]WORK
          WORK is DOUBLE PRECISION array, dimension (3*N**2)
[out]RESULT
          RESULT is DOUBLE PRECISION
          The value RESULT, It is currently limited to 1/ulp, to
          avoid overflow. Errors are flagged by RESULT=10/ulp.
Author
Univ. of Tennessee
Univ. of California Berkeley
Univ. of Colorado Denver
NAG Ltd.