DGSVTS3 tests DGGSVD3, which computes the GSVD of an M-by-N matrix A


 and a P-by-N matrix B:


              U'*A*Q = D1*R and V'*B*Q = D2*R.

M

          M is INTEGER


          The number of rows of the matrix A.  M >= 0.

P

          P is INTEGER


          The number of rows of the matrix B.  P >= 0.

N

          N is INTEGER


          The number of columns of the matrices A and B.  N >= 0.

A

          A is DOUBLE PRECISION array, dimension (LDA,M)


          The M-by-N matrix A.

AF

          AF is DOUBLE PRECISION array, dimension (LDA,N)


          Details of the GSVD of A and B, as returned by DGGSVD3,


          see DGGSVD3 for further details.

LDA

          LDA is INTEGER


          The leading dimension of the arrays A and AF.


          LDA >= max( 1,M ).

B

          B is DOUBLE PRECISION array, dimension (LDB,P)


          On entry, the P-by-N matrix B.

BF

          BF is DOUBLE PRECISION array, dimension (LDB,N)


          Details of the GSVD of A and B, as returned by DGGSVD3,


          see DGGSVD3 for further details.

LDB

          LDB is INTEGER


          The leading dimension of the arrays B and BF.


          LDB >= max(1,P).

U

          U is DOUBLE PRECISION array, dimension(LDU,M)


          The M by M orthogonal matrix U.

LDU

          LDU is INTEGER


          The leading dimension of the array U. LDU >= max(1,M).

V

          V is DOUBLE PRECISION array, dimension(LDV,M)


          The P by P orthogonal matrix V.

LDV

          LDV is INTEGER


          The leading dimension of the array V. LDV >= max(1,P).

Q

          Q is DOUBLE PRECISION array, dimension(LDQ,N)


          The N by N orthogonal matrix Q.

LDQ

          LDQ is INTEGER


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

ALPHA

          ALPHA is DOUBLE PRECISION array, dimension (N)

BETA

          BETA is DOUBLE PRECISION array, dimension (N)


          The generalized singular value pairs of A and B, the


          ``diagonal'' matrices D1 and D2 are constructed from


          ALPHA and BETA, see subroutine DGGSVD3 for details.

R

          R is DOUBLE PRECISION array, dimension(LDQ,N)


          The upper triangular matrix R.

LDR

          LDR is INTEGER


          The leading dimension of the array R. LDR >= max(1,N).

IWORK

          IWORK is INTEGER array, dimension (N)

WORK

          WORK is DOUBLE PRECISION array, dimension (LWORK)

LWORK

          LWORK is INTEGER


          The dimension of the array WORK,


          LWORK >= max(M,P,N)*max(M,P,N).

RWORK

          RWORK is DOUBLE PRECISION array, dimension (max(M,P,N))

RESULT

          RESULT is DOUBLE PRECISION array, dimension (6)


          The test ratios:


          RESULT(1) = norm( U'*A*Q - D1*R ) / ( MAX(M,N)*norm(A)*ULP)


          RESULT(2) = norm( V'*B*Q - D2*R ) / ( MAX(P,N)*norm(B)*ULP)


          RESULT(3) = norm( I - U'*U ) / ( M*ULP )


          RESULT(4) = norm( I - V'*V ) / ( P*ULP )


          RESULT(5) = norm( I - Q'*Q ) / ( N*ULP )


          RESULT(6) = 0        if ALPHA is in decreasing order;


                    = ULPINV   otherwise.

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