SQRT03 tests SORMQR, which computes Q*C, Q'*C, C*Q or C*Q'.


 SQRT03 compares the results of a call to SORMQR with the results of


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


 multiplication by a call to SGEMM.

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 REAL array, dimension (LDA,N)


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


          returned by SGEQRF. See SGEQRF for further details.

C

          C is REAL array, dimension (LDA,N)

CC

          CC is REAL array, dimension (LDA,N)

Q

          Q is REAL array, dimension (LDA,M)

LDA

          LDA is INTEGER


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

TAU

          TAU is REAL array, dimension (min(M,N))


          The scalar factors of the elementary reflectors corresponding


          to the QR factorization in AF.

WORK

          WORK is REAL 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 REAL array, dimension (M)

RESULT

          RESULT is REAL 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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