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Class org.netlib.lapack.DOPGTR

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

public class DOPGTR

extends Object

DOPGTR is a simplified interface to the JLAPACK routine dopgtr.
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
 *  =======
 *
 *  DOPGTR generates a real orthogonal matrix Q which is defined as the
 *  product of n-1 elementary reflectors H(i) of order n, as returned by
 *  DSPTRD using packed storage:
 *
 *  if UPLO = 'U', Q = H(n-1) . . . H(2) H(1),
 *
 *  if UPLO = 'L', Q = H(1) H(2) . . . H(n-1).
 *
 *  Arguments
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          = 'U': Upper triangular packed storage used in previous
 *                 call to DSPTRD;
 *          = 'L': Lower triangular packed storage used in previous
 *                 call to DSPTRD.
 *
 *  N       (input) INTEGER
 *          The order of the matrix Q. N >= 0.
 *
 *  AP      (input) DOUBLE PRECISION array, dimension (N*(N+1)/2)
 *          The vectors which define the elementary reflectors, as
 *          returned by DSPTRD.
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (N-1)
 *          TAU(i) must contain the scalar factor of the elementary
 *          reflector H(i), as returned by DSPTRD.
 *
 *  Q       (output) DOUBLE PRECISION array, dimension (LDQ,N)
 *          The N-by-N orthogonal matrix Q.
 *
 *  LDQ     (input) INTEGER
 *          The leading dimension of the array Q. LDQ >= max(1,N).
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (N-1)
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DOPGTR()

DOPGTR(String, int, double[], double[], double[][], double[], intW)

 public DOPGTR()

 public static void DOPGTR(String uplo,
                           int n,
                           double ap[],
                           double tau[],
                           double q[][],
                           double work[],
                           intW info)

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