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Class org.netlib.lapack.DLACON

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

public class DLACON

extends Object

DLACON is a simplified interface to the JLAPACK routine dlacon.
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
 *  =======
 *
 *  DLACON estimates the 1-norm of a square, real matrix A.
 *  Reverse communication is used for evaluating matrix-vector products.
 *
 *  Arguments
 *  =========
 *
 *  N      (input) INTEGER
 *         The order of the matrix.  N >= 1.
 *
 *  V      (workspace) DOUBLE PRECISION array, dimension (N)
 *         On the final return, V = A*W,  where  EST = norm(V)/norm(W)
 *         (W is not returned).
 *
 *  X      (input/output) DOUBLE PRECISION array, dimension (N)
 *         On an intermediate return, X should be overwritten by
 *               A * X,   if KASE=1,
 *               A' * X,  if KASE=2,
 *         and DLACON must be re-called with all the other parameters
 *         unchanged.
 *
 *  ISGN   (workspace) INTEGER array, dimension (N)
 *
 *  EST    (output) DOUBLE PRECISION
 *         An estimate (a lower bound) for norm(A).
 *
 *  KASE   (input/output) INTEGER
 *         On the initial call to DLACON, KASE should be 0.
 *         On an intermediate return, KASE will be 1 or 2, indicating
 *         whether X should be overwritten by A * X  or A' * X.
 *         On the final return from DLACON, KASE will again be 0.
 *
 *  Further Details
 *  ======= =======
 *
 *  Contributed by Nick Higham, University of Manchester.
 *  Originally named SONEST, dated March 16, 1988.
 *
 *  Reference: N.J. Higham, "FORTRAN codes for estimating the one-norm of
 *  a real or complex matrix, with applications to condition estimation",
 *  ACM Trans. Math. Soft., vol. 14, no. 4, pp. 381-396, December 1988.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLACON()

DLACON(int, double[], double[], int[], doubleW, intW)

 public DLACON()

 public static void DLACON(int n,
                           double v[],
                           double x[],
                           int isgn[],
                           doubleW est,
                           intW kase)

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