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Class org.netlib.lapack.DPPCON

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

public class DPPCON

extends Object

DPPCON is a simplified interface to the JLAPACK routine dppcon.
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
 *  =======
 *
 *  DPPCON estimates the reciprocal of the condition number (in the
 *  1-norm) of a real symmetric positive definite packed matrix using
 *  the Cholesky factorization A = U**T*U or A = L*L**T computed by
 *  DPPTRF.
 *
 *  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
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          = 'U':  Upper triangle of A is stored;
 *          = 'L':  Lower triangle of A is stored.
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  AP      (input) DOUBLE PRECISION array, dimension (N*(N+1)/2)
 *          The triangular factor U or L from the Cholesky factorization
 *          A = U**T*U or A = L*L**T, packed columnwise in a linear
 *          array.  The j-th column of U or L is stored in the array AP
 *          as follows:
 *          if UPLO = 'U', AP(i + (j-1)*j/2) = U(i,j) for 1<=i<=j;
 *          if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = L(i,j) for j<=i<=n.
 *
 *  ANORM   (input) DOUBLE PRECISION
 *          The 1-norm (or infinity-norm) of the symmetric 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 (3*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 ..

DPPCON()

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

 public DPPCON()

 public static void DPPCON(String uplo,
                           int n,
                           double ap[],
                           double anorm,
                           doubleW rcond,
                           double work[],
                           int iwork[],
                           intW info)

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