DQRT03 tests DORMQR, which computes Q*C, Q'*C, C*Q or C*Q'.


 DQRT03 compares the results of a call to DORMQR with the results of


 forming Q explicitly by a call to DORGQR and then performing matrix


 multiplication by a call to DGEMM.

M

          M is INTEGER


          The order of the orthogonal matrix Q.  M >= 0.

N

          N is INTEGER


          The number of rows or columns of the matrix C; C is m-by-n if


          Q is applied from the left, or n-by-m if Q is applied from


          the right.  N >= 0.

K

          K is INTEGER


          The number of elementary reflectors whose product defines the


          orthogonal matrix Q.  M >= K >= 0.

AF

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


          Details of the QR factorization of an m-by-n matrix, as


          returned by DGEQRF. See DGEQRF for further details.

C

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

CC

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

Q

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

LDA

          LDA is INTEGER


          The leading dimension of the arrays AF, C, CC, and Q.

TAU

          TAU is DOUBLE PRECISION array, dimension (min(M,N))


          The scalar factors of the elementary reflectors corresponding


          to the QR factorization in AF.

WORK

          WORK is DOUBLE PRECISION array, dimension (LWORK)

LWORK

          LWORK is INTEGER


          The length of WORK.  LWORK must be at least M, and should be


          M*NB, where NB is the blocksize for this environment.

RWORK

          RWORK is DOUBLE PRECISION array, dimension (M)

RESULT

          RESULT is DOUBLE PRECISION array, dimension (4)


          The test ratios compare two techniques for multiplying a


          random matrix C by an m-by-m orthogonal matrix Q.


          RESULT(1) = norm( Q*C - Q*C )  / ( M * norm(C) * EPS )


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


          RESULT(3) = norm( Q'*C - Q'*C )/ ( M * norm(C) * EPS )


          RESULT(4) = norm( C*Q' - C*Q' )/ ( M * norm(C) * EPS )

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