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Class org.netlib.lapack.DPBSTF

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

public class DPBSTF

extends Object

DPBSTF is a simplified interface to the JLAPACK routine dpbstf.
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
 *  =======
 *
 *  DPBSTF computes a split Cholesky factorization of a real
 *  symmetric positive definite band matrix A.
 *
 *  This routine is designed to be used in conjunction with DSBGST.
 *
 *  The factorization has the form  A = S**T*S  where S is a band matrix
 *  of the same bandwidth as A and the following structure:
 *
 *    S = ( U    )
 *        ( M  L )
 *
 *  where U is upper triangular of order m = (n+kd)/2, and L is lower
 *  triangular of order n-m.
 *
 *  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.
 *
 *  KD      (input) INTEGER
 *          The number of superdiagonals of the matrix A if UPLO = 'U',
 *          or the number of subdiagonals if UPLO = 'L'.  KD >= 0.
 *
 *  AB      (input/output) DOUBLE PRECISION array, dimension (LDAB,N)
 *          On entry, the upper or lower triangle of the symmetric band
 *          matrix A, stored in the first kd+1 rows of the array.  The
 *          j-th column of A is stored in the j-th column of the array AB
 *          as follows:
 *          if UPLO = 'U', AB(kd+1+i-j,j) = A(i,j) for max(1,j-kd)<=i<=j;
 *          if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=min(n,j+kd).
 *
 *          On exit, if INFO = 0, the factor S from the split Cholesky
 *          factorization A = S**T*S. See Further Details.
 *
 *  LDAB    (input) INTEGER
 *          The leading dimension of the array AB.  LDAB >= KD+1.
 *
 *  INFO    (output) INTEGER
 *          = 0: successful exit
 *          < 0: if INFO = -i, the i-th argument had an illegal value
 *          > 0: if INFO = i, the factorization could not be completed,
 *               because the updated element a(i,i) was negative; the
 *               matrix A is not positive definite.
 *
 *  Further Details
 *  ===============
 *
 *  The band storage scheme is illustrated by the following example, when
 *  N = 7, KD = 2:
 *
 *  S = ( s11  s12  s13                     )
 *      (      s22  s23  s24                )
 *      (           s33  s34                )
 *      (                s44                )
 *      (           s53  s54  s55           )
 *      (                s64  s65  s66      )
 *      (                     s75  s76  s77 )
 *
 *  If UPLO = 'U', the array AB holds:
 *
 *  on entry:                          on exit:
 *
 *   *    *   a13  a24  a35  a46  a57   *    *   s13  s24  s53  s64  s75
 *   *   a12  a23  a34  a45  a56  a67   *   s12  s23  s34  s54  s65  s76
 *  a11  a22  a33  a44  a55  a66  a77  s11  s22  s33  s44  s55  s66  s77
 *
 *  If UPLO = 'L', the array AB holds:
 *
 *  on entry:                          on exit:
 *
 *  a11  a22  a33  a44  a55  a66  a77  s11  s22  s33  s44  s55  s66  s77
 *  a21  a32  a43  a54  a65  a76   *   s12  s23  s34  s54  s65  s76   *
 *  a31  a42  a53  a64  a64   *    *   s13  s24  s53  s64  s75   *    *
 *
 *  Array elements marked * are not used by the routine.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DPBSTF()

DPBSTF(String, int, int, double[][], intW)

 public DPBSTF()

 public static void DPBSTF(String uplo,
                           int n,
                           int kd,
                           double ab[][],
                           intW info)

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