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## org.netlib.lapack
Class SPTCON

    java.lang.Object
      org.netlib.lapack.SPTCON

    public class SPTCON

extends java.lang.Object

    SPTCON is a simplified interface to the JLAPACK routine sptcon.
    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
     *  =======
     *
     *  SPTCON computes the reciprocal of the condition number (in the
     *  1-norm) of a real symmetric positive definite tridiagonal matrix
     *  using the factorization A = L*D*L**T or A = U**T*D*U computed by
     *  SPTTRF.
     *
     *  Norm(inv(A)) is computed by a direct method, and the reciprocal of
     *  the condition number is computed as
     *               RCOND = 1 / (ANORM * norm(inv(A))).
     *
     *  Arguments
     *  =========
     *
     *  N       (input) INTEGER
     *          The order of the matrix A.  N >= 0.
     *
     *  D       (input) REAL array, dimension (N)
     *          The n diagonal elements of the diagonal matrix D from the
     *          factorization of A, as computed by SPTTRF.
     *
     *  E       (input) REAL array, dimension (N-1)
     *          The (n-1) off-diagonal elements of the unit bidiagonal factor
     *          U or L from the factorization of A,  as computed by SPTTRF.
     *
     *  ANORM   (input) REAL
     *          The 1-norm of the original matrix A.
     *
     *  RCOND   (output) REAL
     *          The reciprocal of the condition number of the matrix A,
     *          computed as RCOND = 1/(ANORM * AINVNM), where AINVNM is the
     *          1-norm of inv(A) computed in this routine.
     *
     *  WORK    (workspace) REAL array, dimension (N)
     *
     *  INFO    (output) INTEGER
     *          = 0:  successful exit
     *          < 0:  if INFO = -i, the i-th argument had an illegal value
     *
     *  Further Details
     *  ===============
     *
     *  The method used is described in Nicholas J. Higham, "Efficient
     *  Algorithms for Computing the Condition Number of a Tridiagonal
     *  Matrix", SIAM J. Sci. Stat. Comput., Vol. 7, No. 1, January 1986.
     *
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`SPTCON()`

Method Summary
`static void` | `SPTCON(int n, float[] d, float[] e, float anorm, floatW rcond, float[] work, intW info)`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### SPTCON

    public SPTCON()

Method Detail

### SPTCON

    public static void SPTCON(int n,
                              float[] d,
                              float[] e,
                              float anorm,
                              floatW rcond,
                              float[] work,
                              intW info)

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