DORG2L(3f)               LAPACK routine (version 3.1)               DORG2L(3f)



NAME
       DORG2L - an m by n real matrix Q with orthonormal columns,

SYNOPSIS
       SUBROUTINE DORG2L( M, N, K, A, LDA, TAU, WORK, INFO )

           INTEGER        INFO, K, LDA, M, N

           DOUBLE         PRECISION A( LDA, * ), TAU( * ), WORK( * )

PURPOSE
       DORG2L generates an m by n real matrix Q with orthonormal columns,
       which is defined as the last n columns of a product of k elementary
       reflectors of order m

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

       as returned by DGEQLF.


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) DOUBLE PRECISION array, dimension (LDA,N)
               On entry, the (n-k+i)-th column must contain the vector which
               defines the elementary reflector H(i), for i = 1,2,...,k, as
               returned by DGEQLF in the last 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) DOUBLE PRECISION array, dimension (K)
               TAU(i) must contain the scalar factor of the elementary
               reflector H(i), as returned by DGEQLF.

       WORK    (workspace) DOUBLE PRECISION array, dimension (N)

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



 LAPACK routine (version 3.1)    November 2006                      DORG2L(3f)
