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## org.netlib.lapack
Class SPTRFS

    java.lang.Object
      org.netlib.lapack.SPTRFS

    public class SPTRFS

extends java.lang.Object

    SPTRFS is a simplified interface to the JLAPACK routine sptrfs.
    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
     *  =======
     *
     *  SPTRFS improves the computed solution to a system of linear
     *  equations when the coefficient matrix is symmetric positive definite

     *  and tridiagonal, and provides error bounds and backward error
     *  estimates for the solution.
     *
     *  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.
     *
     *  D       (input) REAL array, dimension (N)
     *          The n diagonal elements of the tridiagonal matrix A.
     *
     *  E       (input) REAL array, dimension (N-1)
     *          The (n-1) subdiagonal elements of the tridiagonal matrix A.
     *
     *  DF      (input) REAL array, dimension (N)
     *          The n diagonal elements of the diagonal matrix D from the
     *          factorization computed by SPTTRF.
     *
     *  EF      (input) REAL array, dimension (N-1)
     *          The (n-1) subdiagonal elements of the unit bidiagonal factor

     *          L from the factorization computed by SPTTRF.
     *
     *  B       (input) REAL array, dimension (LDB,NRHS)
     *          The right hand side matrix B.
     *
     *  LDB     (input) INTEGER
     *          The leading dimension of the array B.  LDB >= max(1,N).
     *
     *  X       (input/output) REAL array, dimension (LDX,NRHS)
     *          On entry, the solution matrix X, as computed by SPTTRS.
     *          On exit, the improved solution matrix X.
     *
     *  LDX     (input) INTEGER
     *          The leading dimension of the array X.  LDX >= max(1,N).
     *
     *  FERR    (output) REAL array, dimension (NRHS)
     *          The forward error bound for each solution vector
     *          X(j) (the j-th column of the solution matrix X).
     *          If XTRUE is the true solution corresponding to X(j), FERR(j)

     *          is an estimated upper bound for the magnitude of the largest

     *          element in (X(j) - XTRUE) divided by the magnitude of the
     *          largest element in X(j).
     *
     *  BERR    (output) REAL array, dimension (NRHS)
     *          The componentwise relative backward error of each solution
     *          vector X(j) (i.e., the smallest relative change in
     *          any element of A or B that makes X(j) an exact solution).
     *
     *  WORK    (workspace) REAL array, dimension (2*N)
     *
     *  INFO    (output) INTEGER
     *          = 0:  successful exit
     *          < 0:  if INFO = -i, the i-th argument had an illegal value
     *
     *  Internal Parameters
     *  ===================
     *
     *  ITMAX is the maximum number of steps of iterative refinement.
     *
     *  =====================================================================
     *
     *     .. Parameters ..

Constructor Summary
`SPTRFS()`

Method Summary
`static void` | `SPTRFS(int n, int nrhs, float[] d, float[] e, float[] df, float[] ef, float[][] b, float[][] x, float[] ferr, float[] berr, float[] work, intW info)`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### SPTRFS

    public SPTRFS()

Method Detail

### SPTRFS

    public static void SPTRFS(int n,
                              int nrhs,
                              float[] d,
                              float[] e,
                              float[] df,
                              float[] ef,
                              float[][] b,
                              float[][] x,
                              float[] ferr,
                              float[] berr,
                              float[] work,
                              intW info)

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