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Class org.netlib.lapack.DGETRI

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

public class DGETRI

extends Object

DGETRI is a simplified interface to the JLAPACK routine dgetri.
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
 *  =======
 *
 *  DGETRI computes the inverse of a matrix using the LU factorization
 *  computed by DGETRF.
 *
 *  This method inverts U and then computes inv(A) by solving the system
 *  inv(A)*L = inv(U) for inv(A).
 *
 *  Arguments
 *  =========
 *
 *  N       (input) INTEGER
 *          The order of the matrix A.  N >= 0.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the factors L and U from the factorization
 *          A = P*L*U as computed by DGETRF.
 *          On exit, if INFO = 0, the inverse of the original matrix A.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(1,N).
 *
 *  IPIV    (input) INTEGER array, dimension (N)
 *          The pivot indices from DGETRF; for 1<=i<=N, row i of the
 *          matrix was interchanged with row IPIV(i).
 *
 *  WORK    (workspace/output) DOUBLE PRECISION array, dimension (LWORK)
 *          On exit, if INFO=0, then WORK(1) returns the optimal LWORK.
 *
 *  LWORK   (input) INTEGER
 *          The dimension of the array WORK.  LWORK >= max(1,N).
 *          For optimal performance LWORK >= N*NB, where NB is
 *          the optimal blocksize returned by ILAENV.
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *          > 0:  if INFO = i, U(i,i) is exactly zero; the matrix is
 *                singular and its inverse could not be computed.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DGETRI()

DGETRI(int, double[][], int[], double[], int, intW)

 public DGETRI()

 public static void DGETRI(int n,
                           double a[][],
                           int ipiv[],
                           double work[],
                           int lwork,
                           intW info)

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