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Class org.netlib.lapack.DORGHR

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

public class DORGHR

extends Object

DORGHR is a simplified interface to the JLAPACK routine dorghr.
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
 *  =======
 *
 *  DORGHR generates a real orthogonal matrix Q which is defined as the
 *  product of IHI-ILO elementary reflectors of order N, as returned by
 *  DGEHRD:
 *
 *  Q = H(ilo) H(ilo+1) . . . H(ihi-1).
 *
 *  Arguments
 *  =========
 *
 *  N       (input) INTEGER
 *          The order of the matrix Q. N >= 0.
 *
 *  ILO     (input) INTEGER
 *  IHI     (input) INTEGER
 *          ILO and IHI must have the same values as in the previous call
 *          of DGEHRD. Q is equal to the unit matrix except in the
 *          submatrix Q(ilo+1:ihi,ilo+1:ihi).
 *          1 <= ILO <= IHI <= N, if N > 0; ILO=1 and IHI=0, if N=0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the vectors which define the elementary reflectors,
 *          as returned by DGEHRD.
 *          On exit, the N-by-N orthogonal matrix Q.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A. LDA >= max(1,N).
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (N-1)
 *          TAU(i) must contain the scalar factor of the elementary
 *          reflector H(i), as returned by DGEHRD.
 *
 *  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 >= IHI-ILO.
 *          For optimum performance LWORK >= (IHI-ILO)*NB, where NB is
 *          the optimal blocksize.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DORGHR()

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

 public DORGHR()

 public static void DORGHR(int n,
                           int ilo,
                           int ihi,
                           double a[][],
                           double tau[],
                           double work[],
                           int lwork,
                           intW info)

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