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Class org.netlib.lapack.DGTSV

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

public class DGTSV

extends Object

DGTSV is a simplified interface to the JLAPACK routine dgtsv.
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
 *  =======
 *
 *  DGTSV  solves the equation
 *
 *     A*X = B,
 *
 *  where A is an N-by-N tridiagonal matrix, by Gaussian elimination with
 *  partial pivoting.
 *
 *  Note that the equation  A'*X = B  may be solved by interchanging the
 *  order of the arguments DU and DL.
 *
 *  Arguments
 *  =========
 *
 *  N       (input) INTEGER
 *          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.
 *
 *  DL      (input/output) DOUBLE PRECISION array, dimension (N-1)
 *          On entry, DL must contain the (n-1) subdiagonal elements of
 *          A.
 *          On exit, DL is overwritten by the (n-2) elements of the
 *          second superdiagonal of the upper triangular matrix U from
 *          the LU factorization of A, in DL(1), ..., DL(n-2).
 *
 *  D       (input/output) DOUBLE PRECISION array, dimension (N)
 *          On entry, D must contain the diagonal elements of A.
 *          On exit, D is overwritten by the n diagonal elements of U.
 *
 *  DU      (input/output) DOUBLE PRECISION array, dimension (N-1)
 *          On entry, DU must contain the (n-1) superdiagonal elements
 *          of A.
 *          On exit, DU is overwritten by the (n-1) elements of the first
 *          superdiagonal of U.
 *
 *  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, U(i,i) is exactly zero, and the solution
 *                has not been computed.  The factorization has not been
 *                completed unless i = N.
 *
 *  =====================================================================
 *
 *     .. Parameters ..

DGTSV()

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

 public DGTSV()

 public static void DGTSV(int n,
                          int nrhs,
                          double dl[],
                          double d[],
                          double du[],
                          double b[][],
                          intW info)

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