ZQLT02 tests ZUNGQL, which generates an m-by-n matrix Q with


 orthonormal columns that is defined as the product of k elementary


 reflectors.


 Given the QL factorization of an m-by-n matrix A, ZQLT02 generates


 the orthogonal matrix Q defined by the factorization of the last k


 columns of A; it compares L(m-n+1:m,n-k+1:n) with


 Q(1:m,m-n+1:m)'*A(1:m,n-k+1:n), and checks that the columns of Q are


 orthonormal.

M

          M is INTEGER


          The number of rows of the matrix Q to be generated.  M >= 0.

N

          N is INTEGER


          The number of columns of the matrix Q to be generated.


          M >= N >= 0.

K

          K is INTEGER


          The number of elementary reflectors whose product defines the


          matrix Q. N >= K >= 0.

A

          A is COMPLEX*16 array, dimension (LDA,N)


          The m-by-n matrix A which was factorized by ZQLT01.

AF

          AF is COMPLEX*16 array, dimension (LDA,N)


          Details of the QL factorization of A, as returned by ZGEQLF.


          See ZGEQLF for further details.

Q

          Q is COMPLEX*16 array, dimension (LDA,N)

L

          L is COMPLEX*16 array, dimension (LDA,N)

LDA

          LDA is INTEGER


          The leading dimension of the arrays A, AF, Q and L. LDA >= M.

TAU

          TAU is COMPLEX*16 array, dimension (N)


          The scalar factors of the elementary reflectors corresponding


          to the QL factorization in AF.

WORK

          WORK is COMPLEX*16 array, dimension (LWORK)

LWORK

          LWORK is INTEGER


          The dimension of the array WORK.

RWORK

          RWORK is DOUBLE PRECISION array, dimension (M)

RESULT

          RESULT is DOUBLE PRECISION array, dimension (2)


          The test ratios:


          RESULT(1) = norm( L - Q'*A ) / ( M * norm(A) * EPS )


          RESULT(2) = norm( I - Q'*Q ) / ( M * EPS )

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