CXML
        	    
LAPACK version 3.0
sorgqr(3)

PURPOSE
  SORGQR - generate an M-by-N real matrix Q with orthonormal columns,

SYNTAX
  SUBROUTINE SORGQR( M, N, K, A, LDA, TAU, WORK, LWORK, INFO )

      INTEGER	     INFO, K, LDA, LWORK, M, N

      REAL	     A( LDA, * ), TAU( * ), WORK( * )

DESCRIPTION
  SORGQR generates an M-by-N real matrix Q with orthonormal columns, which is
  defined as the first N columns of a product of K elementary reflectors of
  order M

	Q  =  H(1) H(2) . . . H(k)

  as returned by SGEQRF.

ARGUMENTS
  M	  (input) INTEGER
	  The number of rows of the matrix Q. M >= 0.

  N	  (input) INTEGER
	  The number of columns of the matrix Q. M >= N >= 0.

  K	  (input) INTEGER
	  The number of elementary reflectors whose product defines the
	  matrix Q. N >= K >= 0.

  A	  (input/output) REAL array, dimension (LDA,N)
	  On entry, the i-th column must contain the vector which defines the
	  elementary reflector H(i), for i = 1,2,...,k, as returned by SGEQRF
	  in the first k columns of its array argument A.  On exit, the M-
	  by-N matrix Q.

  LDA	  (input) INTEGER
	  The first dimension of the array A. LDA >= max(1,M).

  TAU	  (input) REAL array, dimension (K)
	  TAU(i) must contain the scalar factor of the elementary reflector
	  H(i), as returned by SGEQRF.

  WORK	  (workspace/output) REAL array, dimension (LWORK)
	  On exit, if INFO = 0, WORK(1) returns the optimal LWORK.

  LWORK	  (input) INTEGER
	  The dimension of the array WORK. LWORK >= max(1,N).  For optimum
	  performance LWORK >= N*NB, where NB is the optimal blocksize.

	  If LWORK = -1, then a workspace query is assumed; the routine only
	  calculates the optimal size of the WORK array, returns this value
	  as the first entry of the WORK array, and no error message related
	  to LWORK is issued by XERBLA.

  INFO	  (output) INTEGER
	  = 0:	successful exit
	  < 0:	if INFO = -i, the i-th argument has an illegal value