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Class org.netlib.lapack.DPOSV

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

public class DPOSV

extends Object

DPOSV is a simplified interface to the JLAPACK routine dposv.
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
 *  =======
 *
 *  DPOSV computes the solution to a real system of linear equations
 *     A * X = B,
 *  where A is an N-by-N symmetric positive definite matrix and X and B
 *  are N-by-NRHS matrices.
 *
 *  The Cholesky decomposition is used to factor A as
 *     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 a lower triangular
 *  matrix.  The factored form of A is then used to solve the system of
 *  equations A * X = B.
 *
 *  Arguments
 *  =========
 *
 *  UPLO    (input) CHARACTER*1
 *          = 'U':  Upper triangle of A is stored;
 *          = 'L':  Lower triangle of A is stored.
 *
 *  N       (input) INTEGER
 *          The number of linear equations, i.e., the order of the
 *          matrix A.  N >= 0.
 *
 *  NRHS    (input) INTEGER
 *          The number of right hand sides, i.e., the number of columns
 *          of the matrix B.  NRHS >= 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).
 *
 *  B       (input/output) DOUBLE PRECISION array, dimension (LDB,NRHS)
 *          On entry, the N-by-NRHS right hand side matrix B.
 *          On exit, if INFO = 0, the N-by-NRHS solution matrix X.
 *
 *  LDB     (input) INTEGER
 *          The leading dimension of the array B.  LDB >= 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 of A is not
 *                positive definite, so the factorization could not be
 *                completed, and the solution has not been computed.
 *
 *  =====================================================================
 *
 *     .. External Functions ..

DPOSV()

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

 public DPOSV()

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

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