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Class org.netlib.lapack.DSPTRI

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

public class DSPTRI

extends Object

DSPTRI is a simplified interface to the JLAPACK routine dsptri.
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
 *  =======
 *
 *  DSPTRI computes the inverse of a real symmetric indefinite matrix
 *  A in packed storage using the factorization A = U*D*U**T or
 *  A = L*D*L**T computed by DSPTRF.
 *
 *  Arguments
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          Specifies whether the details of the factorization are stored
 *          as an upper or lower triangular matrix.
 *          = 'U':  Upper triangular, form is A = U*D*U**T;
 *          = 'L':  Lower triangular, form is A = L*D*L**T.
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  AP      (input/output) DOUBLE PRECISION array, dimension (N*(N+1)/2)
 *          On entry, the block diagonal matrix D and the multipliers
 *          used to obtain the factor U or L as computed by DSPTRF,
 *          stored as a packed triangular matrix.
 *
 *          On exit, if INFO = 0, the (symmetric) inverse of the original
 *          matrix, stored as a packed triangular matrix. The j-th column
 *          of inv(A) is stored in the array AP as follows:
 *          if UPLO = 'U', AP(i + (j-1)*j/2) = inv(A)(i,j) for 1<=i<=j;
 *          if UPLO = 'L',
 *             AP(i + (j-1)*(2n-j)/2) = inv(A)(i,j) for j<=i<=n.
 *
 *  IPIV    (input) INTEGER array, dimension (N)
 *          Details of the interchanges and the block structure of D
 *          as determined by DSPTRF.
 *
 *  WORK    (workspace) DOUBLE PRECISION array, dimension (N)
 *
 *  INFO    (output) INTEGER
 *          = 0: successful exit
 *          < 0: if INFO = -i, the i-th argument had an illegal value
 *          > 0: if INFO = i, D(i,i) = 0; the matrix is singular and its
 *               inverse could not be computed.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DSPTRI()

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

 public DSPTRI()

 public static void DSPTRI(String uplo,
                           int n,
                           double ap[],
                           int ipiv[],
                           double work[],
                           intW info)

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