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Class org.netlib.lapack.DLASQ3

java.lang.Object
   |
   +----org.netlib.lapack.DLASQ3

public class DLASQ3

extends Object

DLASQ3 is a simplified interface to the JLAPACK routine dlasq3.
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
 *     =======
 *
 *     DLASQ3 is the workhorse of the whole bidiagonal SVD algorithm.
 *     This can be described as the differential qd with shifts.
 *
 *     Arguments
 *     =========
 *
 *  N       (input/output) INTEGER
 *          On entry, N specifies the number of rows and columns
 *          in the matrix. N must be at least 3.
 *          On exit N is non-negative and less than the input value.
 *
 *  Q       (input/output) DOUBLE PRECISION array, dimension (N)
 *          Q array in ping (see IPHASE below)
 *
 *  E       (input/output) DOUBLE PRECISION array, dimension (N)
 *          E array in ping (see IPHASE below)
 *
 *  QQ      (input/output) DOUBLE PRECISION array, dimension (N)
 *          Q array in pong (see IPHASE below)
 *
 *  EE      (input/output) DOUBLE PRECISION array, dimension (N)
 *          E array in pong (see IPHASE below)
 *
 *  SUP     (input/output) DOUBLE PRECISION
 *          Upper bound for the smallest eigenvalue
 *
 *  SIGMA   (input/output) DOUBLE PRECISION
 *          Accumulated shift for the present submatrix
 *
 *  KEND    (input/output) INTEGER
 *          Index where minimum D(i) occurs in recurrence for
 *          splitting criterion
 *
 *  OFF     (input/output) INTEGER
 *          Offset for arrays
 *
 *  IPHASE  (input/output) INTEGER
 *          If IPHASE = 1 (ping) then data is in Q and E arrays
 *          If IPHASE = 2 (pong) then data is in QQ and EE arrays
 *
 *  ICONV   (input) INTEGER
 *          If ICONV = 0 a bottom part of a matrix (with a split)
 *          If ICONV =-3 a top part of a matrix (with a split)
 *
 *  EPS     (input) DOUBLE PRECISION
 *          Machine epsilon
 *
 *  TOL2    (input) DOUBLE PRECISION
 *          Square of the relative tolerance TOL as defined in DLASQ1
 *
 *  SMALL2  (input) DOUBLE PRECISION
 *          A threshold value as defined in DLASQ1
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLASQ3()

DLASQ3(intW, double[], double[], double[], double[], doubleW, doubleW, intW, intW, intW, intW, double, double, double)

 public DLASQ3()

 public static void DLASQ3(intW n,
                           double q[],
                           double e[],
                           double qq[],
                           double ee[],
                           doubleW sup,
                           doubleW sigma,
                           intW kend,
                           intW off,
                           intW iphase,
                           intW iconv,
                           double eps,
                           double tol2,
                           double small2)

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