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Class org.netlib.lapack.DPOTRF

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

public class DPOTRF

extends Object

DPOTRF is a simplified interface to the JLAPACK routine dpotrf.
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
 *  =======
 *
 *  DPOTRF computes the Cholesky factorization of a real symmetric
 *  positive definite matrix A.
 *
 *  The factorization has the form
 *     A = U**T * U,  if UPLO = 'U', or
 *     A = L  * L**T,  if UPLO = 'L',
 *  where U is an upper triangular matrix and L is lower triangular.
 *
 *  This is the block version of the algorithm, calling Level 3 BLAS.
 *
 *  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.
 *
 *  A       (input/output) DOUBLE PRECISION array, dimension (LDA,N)
 *          On entry, the symmetric matrix A.  If UPLO = 'U', the leading
 *          N-by-N upper triangular part of A contains the upper
 *          triangular part of the matrix A, and the strictly lower
 *          triangular part of A is not referenced.  If UPLO = 'L', the
 *          leading N-by-N lower triangular part of A contains the lower
 *          triangular part of the matrix A, and the strictly upper
 *          triangular part of A is not referenced.
 *
 *          On exit, if INFO = 0, the factor U or L from the Cholesky
 *          factorization A = U**T*U or A = L*L**T.
 *
 *  LDA     (input) INTEGER
 *          The leading dimension of the array A.  LDA >= max(1,N).
 *
 *  INFO    (output) INTEGER
 *          = 0:  successful exit
 *          < 0:  if INFO = -i, the i-th argument had an illegal value
 *          > 0:  if INFO = i, the leading minor of order i is not
 *                positive definite, and the factorization could not be
 *                completed.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DPOTRF()

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

 public DPOTRF()

 public static void DPOTRF(String uplo,
                           int n,
                           double a[][],
                           intW info)

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