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Class org.netlib.lapack.DGEQRS

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

public class DGEQRS

extends Object

DGEQRS is a simplified interface to the JLAPACK routine dgeqrs.
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
 *  =======
 *
 *  Solve the least squares problem
 *      min || A*X - B ||
 *  using the QR factorization
 *      A = Q*R
 *  computed by DGEQRF.
 *
 *  Arguments
 *  =========
 *
 *  M       (input) INTEGER
 *          The number of rows of the matrix A.  M >= 0.
 *
 *  N       (input) INTEGER
 *          The number of columns of the matrix A.  M >= N >= 0.
 *
 *  NRHS    (input) INTEGER
 *          The number of columns of B.  NRHS >= 0.
 *
 *  A       (input) DOUBLE PRECISION array, dimension (LDA,N)
 *          Details of the QR factorization of the original matrix A as
 *          returned by DGEQRF.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= M.
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (N)
 *          Details of the orthogonal matrix Q.
 *
 *  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
 *          On entry, the m-by-nrhs right hand side matrix B.
 *          On exit, the n-by-nrhs solution matrix X.
 *
 *  LDB     (input) INTEGER
 *          The leading dimension of the array B. LDB >= M.
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (LWORK)
 *
 *  LWORK   (input) INTEGER
 *          The length of the array WORK.  LWORK must be at least NRHS,
 *          and should be at least NRHS*NB, where NB is the block size
 *          for this environment.
 *
 *  INFO    (output) INTEGER
 *          = 0: successful exit
 *          < 0: if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DGEQRS()

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

 public DGEQRS()

 public static void DGEQRS(int m,
                           int n,
                           int nrhs,
                           double a[][],
                           double tau[],
                           double b[][],
                           double work[],
                           int lwork,
                           intW info)

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