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## org.netlib.lapack
Class DSBGST

    java.lang.Object
      org.netlib.lapack.DSBGST

    public class DSBGST

extends java.lang.Object

    DSBGST is a simplified interface to the JLAPACK routine dsbgst.
    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
     *  =======
     *
     *  DSBGST reduces a real symmetric-definite banded generalized
     *  eigenproblem  A*x = lambda*B*x  to standard form  C*y = lambda*y,
     *  such that C has the same bandwidth as A.
     *
     *  B must have been previously factorized as S**T*S by DPBSTF, using a
     *  split Cholesky factorization. A is overwritten by C = X**T*A*X, where
     *  X = S**(-1)*Q and Q is an orthogonal matrix chosen to preserve the
     *  bandwidth of A.
     *
     *  Arguments
     *  =========
     *
     *  VECT    (input) CHARACTER*1
     *          = 'N':  do not form the transformation matrix X;
     *          = 'V':  form X.
     *
     *  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 matrices A and B.  N >= 0.
     *
     *  KA      (input) INTEGER
     *          The number of superdiagonals of the matrix A if UPLO = 'U',
     *          or the number of subdiagonals if UPLO = 'L'.  KA >= 0.
     *
     *  KB      (input) INTEGER
     *          The number of superdiagonals of the matrix B if UPLO = 'U',
     *          or the number of subdiagonals if UPLO = 'L'.  KA >= KB >= 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 ka+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(ka+1+i-j,j) = A(i,j) for max(1,j-ka)<=i<=j;
     *          if UPLO = 'L', AB(1+i-j,j)    = A(i,j) for j<=i<=min(n,j+ka).
     *
     *          On exit, the transformed matrix X**T*A*X, stored in the same

     *          format as A.
     *
     *  LDAB    (input) INTEGER
     *          The leading dimension of the array AB.  LDAB >= KA+1.
     *
     *  BB      (input) DOUBLE PRECISION array, dimension (LDBB,N)
     *          The banded factor S from the split Cholesky factorization of

     *          B, as returned by DPBSTF, stored in the first KB+1 rows of
     *          the array.
     *
     *  LDBB    (input) INTEGER
     *          The leading dimension of the array BB.  LDBB >= KB+1.
     *
     *  X       (output) DOUBLE PRECISION array, dimension (LDX,N)
     *          If VECT = 'V', the n-by-n matrix X.
     *          If VECT = 'N', the array X is not referenced.
     *
     *  LDX     (input) INTEGER
     *          The leading dimension of the array X.
     *          LDX >= max(1,N) if VECT = 'V'; LDX >= 1 otherwise.
     *
     *  WORK    (workspace) DOUBLE PRECISION array, dimension (2*N)
     *
     *  INFO    (output) INTEGER
     *          = 0:  successful exit
     *          < 0:  if INFO = -i, the i-th argument had an illegal value.
     *
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`DSBGST()`

Method Summary
`static void` | `DSBGST(java.lang.String vect, java.lang.String uplo, int n, int ka, int kb, double[][] ab, double[][] bb, double[][] x, double[] work, intW info)`

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

Constructor Detail

### DSBGST

    public DSBGST()

Method Detail

### DSBGST

    public static void DSBGST(java.lang.String vect,
                              java.lang.String uplo,
                              int n,
                              int ka,
                              int kb,
                              double[][] ab,
                              double[][] bb,
                              double[][] x,
                              double[] work,
                              intW info)

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