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Class org.netlib.lapack.DGTCON

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

public class DGTCON

extends Object

DGTCON is a simplified interface to the JLAPACK routine dgtcon.
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
 *  =======
 *
 *  DGTCON estimates the reciprocal of the condition number of a real
 *  tridiagonal matrix A using the LU factorization as computed by
 *  DGTTRF.
 *
 *  An estimate is obtained for norm(inv(A)), and the reciprocal of the
 *  condition number is computed as RCOND = 1 / (ANORM * norm(inv(A))).
 *
 *  Arguments
 *  =========
 *
 *  NORM    (input) CHARACTER*1
 *          Specifies whether the 1-norm condition number or the
 *          infinity-norm condition number is required:
 *          = '1' or 'O':  1-norm;
 *          = 'I':         Infinity-norm.
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  DL      (input) DOUBLE PRECISION array, dimension (N-1)
 *          The (n-1) multipliers that define the matrix L from the
 *          LU factorization of A as computed by DGTTRF.
 *
 *  D       (input) DOUBLE PRECISION array, dimension (N)
 *          The n diagonal elements of the upper triangular matrix U from
 *          the LU factorization of A.
 *
 *  DU      (input) DOUBLE PRECISION array, dimension (N-1)
 *          The (n-1) elements of the first superdiagonal of U.
 *
 *  DU2     (input) DOUBLE PRECISION array, dimension (N-2)
 *          The (n-2) elements of the second superdiagonal of U.
 *
 *  IPIV    (input) INTEGER array, dimension (N)
 *          The pivot indices; for 1 <= i <= n, row i of the matrix was
 *          interchanged with row IPIV(i).  IPIV(i) will always be either
 *          i or i+1; IPIV(i) = i indicates a row interchange was not
 *          required.
 *
 *  ANORM   (input) DOUBLE PRECISION
 *          If NORM = '1' or 'O', the 1-norm of the original matrix A.
 *          If NORM = 'I', the infinity-norm of the original matrix A.
 *
 *  RCOND   (output) DOUBLE PRECISION
 *          The reciprocal of the condition number of the matrix A,
 *          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is an
 *          estimate of the 1-norm of inv(A) computed in this routine.
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (2*N)
 *
 *  IWORK   (workspace) INTEGER array, dimension (N)
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DGTCON()

DGTCON(String, int, double[], double[], double[], double[], int[], double, doubleW, double[], int[], intW)

 public DGTCON()

 public static void DGTCON(String norm,
                           int n,
                           double dl[],
                           double d[],
                           double du[],
                           double du2[],
                           int ipiv[],
                           double anorm,
                           doubleW rcond,
                           double work[],
                           int iwork[],
                           intW info)

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