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Class org.netlib.lapack.DLAQSY

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

public class DLAQSY

extends Object

DLAQSY is a simplified interface to the JLAPACK routine dlaqsy.
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
 *  =======
 *
 *  DLAQSY equilibrates a symmetric matrix A using the scaling factors
 *  in the vector S.
 *
 *  Arguments
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          Specifies whether the upper or lower triangular part of the
 *          symmetric matrix A is stored.
 *          = 'U':  Upper triangular
 *          = 'L':  Lower triangular
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the symmetric matrix A.  If UPLO = 'U', the leading
 *          n by n upper triangular part of A contains the upper
 *          triangular part of the matrix A, and the strictly lower
 *          triangular part of A is not referenced.  If UPLO = 'L', the
 *          leading n by n lower triangular part of A contains the lower
 *          triangular part of the matrix A, and the strictly upper
 *          triangular part of A is not referenced.
 *
 *          On exit, if EQUED = 'Y', the equilibrated matrix:
 *          diag(S) * A * diag(S).
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(N,1).
 *
 *  S       (input) DOUBLE PRECISION array, dimension (N)
 *          The scale factors for A.
 *
 *  SCOND   (input) DOUBLE PRECISION
 *          Ratio of the smallest S(i) to the largest S(i).
 *
 *  AMAX    (input) DOUBLE PRECISION
 *          Absolute value of largest matrix entry.
 *
 *  EQUED   (output) CHARACTER*1
 *          Specifies whether or not equilibration was done.
 *          = 'N':  No equilibration.
 *          = 'Y':  Equilibration was done, i.e., A has been replaced by
 *                  diag(S) * A * diag(S).
 *
 *  Internal Parameters
 *  ===================
 *
 *  THRESH is a threshold value used to decide if scaling should be done
 *  based on the ratio of the scaling factors.  If SCOND < THRESH,
 *  scaling is done.
 *
 *  LARGE and SMALL are threshold values used to decide if scaling should
 *  be done based on the absolute size of the largest matrix element.
 *  If AMAX > LARGE or AMAX < SMALL, scaling is done.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DLAQSY()

DLAQSY(String, int, double[][], double[], double, double, StringW)

 public DLAQSY()

 public static void DLAQSY(String uplo,
                           int n,
                           double a[][],
                           double s[],
                           double scond,
                           double amax,
                           StringW equed)

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