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Class org.netlib.lapack.DQRT11

java.lang.Object
   |
   +----org.netlib.lapack.DQRT11

public class DQRT11

extends Object

DQRT11 is a simplified interface to the JLAPACK routine dqrt11.
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
 *  =======
 *
 *  DQRT11 computes the test ratio
 *
 *        || Q'*Q - I || / (eps * m)
 *
 *  where the orthogonal matrix Q is represented as a product of
 *  elementary transformations.  Each transformation has the form
 *
 *     H(k) = I - tau(k) v(k) v(k)'
 *
 *  where tau(k) is stored in TAU(k) and v(k) is an m-vector of the form
 *  [ 0 ... 0 1 x(k) ]', where x(k) is a vector of length m-k stored
 *  in A(k+1:m,k).
 *
 *  Arguments
 *  =========
 *
 *  M       (input) INTEGER
 *          The number of rows of the matrix A.
 *
 *  K       (input) INTEGER
 *          The number of columns of A whose subdiagonal entries
 *          contain information about orthogonal transformations.
 *
 *  A       (input) DOUBLE PRECISION array, dimension (LDA,K)
 *          The (possibly partial) output of a QR reduction routine.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.
 *
 *  TAU     (input) DOUBLE PRECISION array, dimension (K)
 *          The scaling factors tau for the elementary transformations as
 *          computed by the QR factorization routine.
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (LWORK)
 *
 *  LWORK   (input) INTEGER
 *          The length of the array WORK.  LWORK >= M*M + M.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DQRT11()

DQRT11(int, int, double[][], double[], double[], int)

 public DQRT11()

 public static double DQRT11(int m,
                             int k,
                             double a[][],
                             double tau[],
                             double work[],
                             int lwork)

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