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Class org.netlib.lapack.DSPGST

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

public class DSPGST

extends Object

DSPGST is a simplified interface to the JLAPACK routine dspgst.
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
 *  =======
 *
 *  DSPGST reduces a real symmetric-definite generalized eigenproblem
 *  to standard form, using packed storage.
 *
 *  If ITYPE = 1, the problem is A*x = lambda*B*x,
 *  and A is overwritten by inv(U**T)*A*inv(U) or inv(L)*A*inv(L**T)
 *
 *  If ITYPE = 2 or 3, the problem is A*B*x = lambda*x or
 *  B*A*x = lambda*x, and A is overwritten by U*A*U**T or L**T*A*L.
 *
 *  B must have been previously factorized as U**T*U or L*L**T by DPPTRF.
 *
 *  Arguments
 *  =========
 *
 *  ITYPE   (input) INTEGER
 *          = 1: compute inv(U**T)*A*inv(U) or inv(L)*A*inv(L**T);
 *          = 2 or 3: compute U*A*U**T or L**T*A*L.
 *
 *  UPLO    (input) CHARACTER
 *          = 'U':  Upper triangle of A is stored and B is factored as
 *                  U**T*U;
 *          = 'L':  Lower triangle of A is stored and B is factored as
 *                  L*L**T.
 *
 *  N       (input) INTEGER
 *          The order of the matrices A and B.  N >= 0.
 *
 *  AP      (input/output) DOUBLE PRECISION array, dimension (N*(N+1)/2)
 *          On entry, the upper or lower triangle of the symmetric matrix
 *          A, packed columnwise in a linear array.  The j-th column of A
 *          is stored in the array AP as follows:
 *          if UPLO = 'U', AP(i + (j-1)*j/2) = A(i,j) for 1<=i<=j;
 *          if UPLO = 'L', AP(i + (j-1)*(2n-j)/2) = A(i,j) for j<=i<=n.
 *
 *          On exit, if INFO = 0, the transformed matrix, stored in the
 *          same format as A.
 *
 *  BP      (input) DOUBLE PRECISION array, dimension (N*(N+1)/2)
 *          The triangular factor from the Cholesky factorization of B,
 *          stored in the same format as A, as returned by DPPTRF.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DSPGST()

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

 public DSPGST()

 public static void DSPGST(int itype,
                           String uplo,
                           int n,
                           double ap[],
                           double bp[],
                           intW info)

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