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Class org.netlib.lapack.DORGRQ

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

public class DORGRQ

extends Object

DORGRQ is a simplified interface to the JLAPACK routine dorgrq.
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
 *  =======
 *
 *  DORGRQ generates an M-by-N real matrix Q with orthonormal rows,
 *  which is defined as the last M rows of a product of K elementary
 *  reflectors of order N
 *
 *        Q  =  H(1) H(2) . . . H(k)
 *
 *  as returned by DGERQF.
 *
 *  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. N >= M.
 *
 *  K       (input) INTEGER
 *          The number of elementary reflectors whose product defines the
 *          matrix Q. M >= K >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the (m-k+i)-th row must contain the vector which
 *          defines the elementary reflector H(i), for i = 1,2,...,k, as
 *          returned by DGERQF in the last k rows 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 DGERQF.
 *
 *  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,M).
 *          For optimum performance LWORK >= M*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 ..

DORGRQ()

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

 public DORGRQ()

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

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