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Class org.netlib.lapack.DORGQR

java.lang.Object
   |
   +----org.netlib.lapack.DORGQR

public class DORGQR

extends Object

DORGQR is a simplified interface to the JLAPACK routine dorgqr.
This interface converts Java-style 2D row-major arrays into
the 1D column-major linearized arrays expected by the lower
level JLAPACK routines.  Using this interface also allows you
to omit offset and leading dimension arguments.  However, because
of these conversions, these routines will be slower than the low
level ones.  Following is the description from the original Fortran
source.  Contact seymour@cs.utk.edu with any questions.

 *     ..
 *
 *  Purpose
 *  =======
 *
 *  DORGQR 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 DGEQRF.
 *
 *  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 i-th column must contain the vector which
 *          defines the elementary reflector H(i), for i = 1,2,...,k, as
 *          returned by DGEQRF 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) DOUBLE PRECISION array, dimension (K)
 *          TAU(i) must contain the scalar factor of the elementary
 *          reflector H(i), as returned by DGEQRF.
 *
 *  WORK    (workspace/output) DOUBLE PRECISION 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.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument has an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DORGQR()

DORGQR(int, int, int, double[][], double[], double[], int, intW)

 public DORGQR()

 public static void DORGQR(int m,
                           int n,
                           int k,
                           double a[][],
                           double tau[],
                           double work[],
                           int lwork,
                           intW info)

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